JP2003090628A - Bathtub water circulating connection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To assure safety even in the case wherein a bathtub water circulating connection device is used without installing a bathtub filter. SOLUTION: A bathtub water passage separately-forming member 32 constituting a bathtub water circulating connection device has a first water passage 34 and a second water passage 36 which are provided with outer peripheral openings 33 and 35. A plurality of negative pressure alleviating openings 37 are provided adjacently. If the bathtub water circulating connection device is used without installing the bathtub filter, safe bathing is assured because hairs of a child or the like can be got out of the openings 33 and 35 by a weak force even if the hairs of the child should be sucked in the openings 33 and 35.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in a through hole in a wall surface of a bathtub in order to forcibly circulate hot water in the bathtub water between a bathtub and a device with a built-in pump such as a forced circulation water heater. It relates to a bath water circulation connection device.

[0002]

2. Description of the Related Art Conventionally, a bathtub water circulation connecting device of this type has a built-in pump such as a forced circulation type water heater installed in a through hole in a wall surface of a bathtub installed in each home or the like. The equipment is connected to the equipment to forcibly circulate hot water from the bath water.

In FIG. 8, a bath water circulation connection device A is attached to a through hole in the side wall of the bath tub 1, and a hot and cold water return connection pipe 5,
A typical example in which the hot and cold water connection pipe 6 and the extension connection pipes 9 and 10 are respectively connected and the bath water 2 circulates through the extension connection pipes 9 and 10 when the circulation pump 12 connected to the pump built-in device 11 operates. Here is an example of such construction.

FIG. 9 shows an example of a general component construction of the bath water circulation connection device A, which shows a through hole 18 in the side wall of the bath 1.
The connecting body 20 is arranged from the outer wall 1 of the bathtub via the airtight packing 19, and the fixing screw 14 is screwed into the connecting body 20 from the inside of the bathtub via the airtight sheet 16 and the flat packing 17. . And a bathtub water passage separation forming tool 1 resin-molded on a boss provided on the front surface of the fixing screw 14.
3 is attached with three screws 15, and the bathtub filter 3 is finally attached.

Further, FIGS. 10 (a), 10 (b) and 11
Is a general front schematic configuration diagram of a bathtub water passage separation forming tool related to the present invention, a schematic configuration view of the outer peripheral openings 7 and 8 seen from the front, and a bathtub filter 3 attached to the bathtub water passage separation forming tool 13. FIG. 3 is a schematic view of the inner surface of the bathtub water circulation connection device between the bathtub 2 and the device 11 with a built-in pump.
A bathtub water passage separation forming tool 13 having a first water passage 21 and a second water passage 22 for circulating return water is provided, and a bathtub water passage separation forming tool 13 composed of each of the water passages and an oval shape on the outer periphery thereof. Openings 23 and 24 are provided.

A bathtub filter 3 is mounted inside the bathtub 1 of the bathtub water passage separation forming tool 13, and filters 25 and 26 for circulating hot and cold water are provided on the front and outer peripheral portions of the bathtub filter 3, respectively. .

The circulation pump 1 of the device 11 with a built-in pump
When 2 is operated, the bath water 2 of the bathtub 1 passes through the bathtub filter 3, the outer peripheral opening 23 of the bathtub water passage separation forming tool 13, the first water passage 21, the return connection pipe 5, the return extension connection pipe 9, and the pump built-in device. 11 circulation pump 12, forward extension connecting pipe 1
0, the outward connection pipe 6, the second water passage 22 of the bathtub water passage separation forming tool 13, the outer peripheral opening 24, and the bathtub filter 3 to forcefully circulate between the bathtub 1 and the pump-equipped device 11.

At this time, the above-mentioned bathtub water passage separation forming tool 1
The bath water is sucked in through the suction opening 23 provided in the outer peripheral portion of the bathtub 3, and the bathwater 2 heated by, for example, a hot water supply device with a built-in pump is discharged through the other discharge opening 24, so that the bathwater 2
Is stirred and circulated to boil the bath water 2 uniformly. In order to perform the stirring circulation more efficiently, the first water passage 21 and the second water passage 22 are discharged to the bottom surface side of the bathtub 1 in a substantially eight shape,
The bath water 2 on the bottom surface is agitated.

[0009]

However, in the structure of the conventional bathtub water passage separation forming tool, increasing the opening area of the suction and discharge openings provided on the outer periphery is not limited to the shape of the bathtub water passage separation forming tool. Since the outside diameter of the bathtub filter to be attached to the bathtub water passage separation forming tool is generally φ90 mm to φ100 mm, the opening area of the suction and discharge openings is necessarily 60 mm ² to 80 mm. ^{2, which} is relatively small, so that the negative pressure suction force of the suction opening due to the circulation flow rate of the circulation pump becomes large.

In normal use, since the bathtub filter is attached to the outer peripheral portion of the bathtub water passage separation forming tool, foreign matter (dust, lint, hair, etc.) in the bathtub water is sucked into the suction opening at the filter portion of the bathtub filter. It is possible to secure reliability due to foreign matter being clogged in and the foreign matter flowing into the circulation pump.

However, when it is used without removing it for cleaning or washing the filter portion of the bathtub filter,
When the suction opening is exposed, for example, when a child dives and plays in the bathtub, hair and a part of clothes are sucked into the suction opening and become blocked, which impairs the circulation action of the circulation pump and causes a failure. On the other hand, there is a problem that hair is sucked in the worst state and the hair cannot be removed due to the negative pressure of the suction of the circulation pump, which may cause a child to drown.

The present invention is intended to solve the above-mentioned conventional problems. To ensure the circulating action of bath water and eliminate pump failure even when the bath filter in abnormal use is removed and used. An object of the present invention is to provide a safe bathtub water circulation connecting device by configuring a bathtub water passage separator that can be immediately removed with a weak force even if foreign matter such as hair of a person taking a bath is sucked.

[0013]

In order to solve the above-mentioned conventional problems, the present invention is a bathtub attached to a through hole in a wall surface of a bathtub for forcibly circulating the bathwater between the bathtub and the circulation pump. A water circulation connector, comprising a bath water passage separation forming tool having a first water passage on the suction side of bath water and a second water passage on the discharge side of bath water, wherein the first water passage comprises:
The bath water passage separation forming tool has a suction opening opening to the outer periphery, the second water passage has a discharge opening opening to the outer circumference of the bath water passage separating formation tool, and the suction opening of the first water passage. Further, a part of the bathtub water passage separation forming tool adjacent to the discharge opening of the second water passage is provided with a plurality of negative pressure reducing openings smaller than the suction opening and the discharge opening.

Thus, in addition to the outer peripheral opening of the bath water passage separation forming tool, a plurality of negative pressures smaller than the suction opening and the discharge opening are reduced in a part of the bath water passage separating formation adjacent to the outer peripheral opening. By providing the opening, even when foreign matter is sucked into the outer peripheral opening and the outer peripheral opening is closed, the bath water can be sucked from the plurality of negative pressure reducing openings adjacent to the outer peripheral opening.

Accordingly, in such a case, the suction force of the outer peripheral opening is remarkably increased by ensuring the suction circulation action of the bath water and the pump circulation action even if, for example, the hair of the child is sucked as foreign matter. It is possible to easily remove the hair with a weak force, the water accident due to the hair being sucked in the bathtub is eliminated, and the safety can be secured more than before.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention according to claim 1 is a bathtub water circulation system which is attached to a through hole in a wall surface portion of a bathtub and forcibly circulates bathtub water between a bathtub and a hot water supply apparatus having a circulation pump built therein. A connecting tool, comprising a bathtub water passage separation forming tool having a first water passage on the suction side of the bath water and a second water passage on the discharge side of the bath water, wherein the first water passage is the bath water. The second water passage has a discharge opening opening to the outer circumference of the bathtub water passage separation forming tool, and the second water passage has a suction opening opening to the outer circumference of the passage separation forming tool. A part of the bathtub water passage separation forming tool adjacent to the discharge opening of the two water passages is provided with a plurality of negative pressure reducing openings smaller than the suction or discharge openings.

According to this aspect, the circulation action of the pump is secured by the plurality of openings provided adjacent to the outer peripheral opening,
While the durability of the pump is improved, the suction force at the outer peripheral opening is reduced, that is, the negative pressure is reduced and the suction force exerted on the hair is weakened, so even if the hair is inhaled, the removal force is reduced, The safety can be further improved.

Further, the invention according to claim 2 particularly reduces adjacent negative pressure by forming a plurality of openings adjacent to the outer peripheral opening according to claim 1 and having the same or different shape. It is possible to further reduce the negative pressure of the opening, reduce the die cost, and improve the productivity.

According to the third aspect of the invention, in particular, the area S1 of the negative pressure reducing opening of the same or different shape is 60 with respect to the opening area S of the suction opening and the discharge opening of the second aspect.
By setting it in the range of up to 150%, the suction negative pressure can be reduced more effectively.

Further, in the invention described in claim 4, in particular, the modified negative pressure reducing opening according to claim 1 having a large opening is separated farthest from the outer peripheral suction opening and the outer peripheral discharge opening. By providing it at a high position, the suction negative pressure is reduced, and the suction is remarkably reduced as the hair or the like floats in the suction opening of the outer peripheral portion.

Further, the invention according to claim 5 is characterized in that the adjoining front surface negative pressure reducing opening according to claim 1 is formed into a flat shape to prevent a short circuit when the bathtub filter is attached, With bathtub filter attached,
It is possible to prevent a short circuit from the suction opening and the discharge opening on the front surface and significantly improve the blocking effect.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is an exploded perspective view of a bath water circulation connection apparatus according to Embodiment 1 of the present invention, and FIG.
(A) (b) is a schematic front view of a bathtub water passage separation forming tool which comprises a bathtub water circulation connecting device, and a schematic front view of a plurality of negative pressure reducing openings adjacent to the outer peripheral opening of the bathtub water passage separating and forming tool. The figures are respectively shown.

In the invention of the present embodiment, parts having the same constructions and effects as those of the conventional construction will be designated by the same reference numerals, detailed description thereof will be omitted, and different portions will be mainly described.

In FIGS. 1 and 2, reference numeral 32 denotes a bathtub water passage separation forming tool (resin molded product) of the present invention, which is a first water passage 34 in the front surface adjacent to the suction opening 33 and the discharge opening 35 in the outer peripheral portion. The second water passage 36 and the second water passage 36 are provided with a plurality of negative pressure reducing openings 35 and 37 having the same shape and the same number, and the bathtub water passage separation forming tool 32 is normally used with the bathtub filter 31 attached. This is the configuration.

In the bathtub water passage shown in FIG. 3, as another construction in which a plurality of negative pressure reducing openings 35, 37 are provided on the front surface of the bathtub water passage separation forming tool 32 configured as described above. In addition to the separation forming tool 32 (round negative pressure reducing openings 35, 37), (a) bath water passage separation forming tool 41 (angle negative pressure reducing openings 46, 47), (b) bath water passage separation forming Ingredient 48
A representative example of the same shape of the (two rows of round negative pressure reducing openings 53, 54) is shown.

Further, in FIG. 4, the bath water passage separation forming tool 55 of (a) is a combination of two types of large negative pressure reducing openings 60 and 61 and small negative pressure reducing openings 62 and 63, and bath water of (b). The passage separation forming tool 64 is a combination of two types of angular negative pressure reducing openings 69 and 70 and round negative pressure reducing openings 71 and 72, and the bath water passage separating forming tool 73 in (c) is a slit type negative pressure reducing opening. Representative examples of deformed shapes of two kinds of combinations 78, 79 and round negative pressure reducing openings 80, 81 are shown.

Although not shown in the drawing, in addition to the two types of irregular shapes, three types and four types are also within the scope of the present invention.

First, when the bathtub filter is installed, since it is generally used normally, there is a difference in the action and effect between the conventional bathtub water passage separation forming tool and the present invention's bathtub water passage separation forming tool. There is no. Under the worst condition where the bathtub filter is removed, the presence or absence of the negative pressure reducing opening is provided in a part of the first and second water passages on the front surface adjacent to the suction and discharge openings on the outer periphery of the bathtub water passage separation forming tool. The difference is clear. By providing a plurality of negative pressure reducing openings of the present invention, for example, when a child dives and the hair is sucked into the suction opening on the outer circumference as a foreign substance, the conventional product having only one suction opening has At the stage of being sucked, negative pressure corresponding to the whole stroke of the circulation pump is applied, hair is deeper than the opening and a large amount is sucked in, and under the pulling force of the child, a large negative pressure state is impossible and hair is pulled from the opening. Sometimes it cannot be removed.

On the other hand, by providing a plurality of negative pressure reducing openings in the front surface in addition to the outer peripheral opening, even if hair is sucked in, a negative pressure is applied to a part of the toothbrush of the circulation pump. The remaining tooth flow flows in through the opening of, and the negative pressure is reduced. As a result, the hair stays in the vicinity of the opening and is sucked in a small amount, and the action and effect that the hair can be immediately removed by the pulling force of the child is produced.

Even when the negative pressure reducing opening shapes of the front opening portion are the same or different, the same hair as described above stays in the vicinity of the opening portion and sucks a small amount.
Even the pulling force of the child has the effect of allowing immediate removal of the hair.

(Embodiment 2) FIG. 5 shows a schematic diagram of measurement of tensile force by forced inhalation of hair for evaluation (effect) judgment of the present invention, and details are JIS C 9335-2-.
Based on the individual requirements for 60 whirlpool bathtubs (established 2000/9/20), the worst conditions were removed with the bathtub filter removed.

(Schematic test method) Forcibly hair 86 [diameter 25 mm * free portion 400 mm]
To be completely sucked into the suction opening 82. Vertically above the bathtub water passage separation forming tool 81 (below 9
The rod 87 is pulled in the direction of 0 °), and the pulling force with which the hair 86 comes off is measured with a spring gage 88 (0 to 5 Kgf). For the bathtub water passage separation forming tool 81, the front upper 40 ° (hereinafter referred to as 40 ° direction) (judgment standard) It was carried out 5 times in both 90 ° direction and 40 ° direction, and 20N (about 2
Kgf) or less.

(Reference) 20N means 2Kgf * 9.8 = 19.6N≈20N.

Table 1 shows the negative opening area S1 and the outer circumference of the negative opening depending on the number of circular opening shapes * of the negative opening openings 84 and 85 of the same shape provided on the front surface of the bath water passage separation forming tool 81. The area S of the suction opening portion 82 provided in FIG.

At this time, the outer peripheral opening 82 has a rectangular shape of 7 mm * 10 mm = 70 mm ² , and the circulation flow rate of the circulation pump is 10 L / min (generally, a bath water heating device using electric power, gas, or oil as a heat source). The circulation pump used in the case of a short bath connection pipe of about 1 m) is assumed.

[0037]

[Table 1]

As is clear from (Table 1), S1 / S
If the ratio is 50% or more, the hair can be easily removed with a tensile force of 20 N or less.

The S1 / S ratio is preferably 60% or more. On the other hand, when S1 / S is 150% or more, the amount of hair sucked from the front opening becomes larger than that of the outer peripheral opening, and the hair sucked from the plurality of negative pressure reducing openings flows in a turbulent flow, and In the part, the tendency for the hair to become entangled becomes remarkable, which becomes a factor of deteriorating the tensile force. Therefore, the preferable S1 / S ratio is 130% or less.

When a plurality of openings are round negative pressure reducing openings, in addition to the above S1 / S ratio of 50%, it is desirable that the same shape has a diameter of 2 mm to 3.3 mm, and more preferably 2.5 mm. The range is φ3 mm. If it is less than φ2, in order to secure the S1 / S ratio of 50% or more, the resin molding opening pin will be thin and the pin life will be shortened (including pin breakage, etc.) and the total pin processing cost will be included. It is not preferable because the mold cost becomes high. On the other hand, if it is φ3.3 mm or more, it is easy to set the S1 / S ratio to 50% or more, and there is an advantage that the life of the pin is improved and the total die cost is low, but the round opening becomes large and In addition to the openings, the amount of hair sucked into multiple negative pressure relief openings adjacent to the outer circumference also increases, which tends to cause hair entanglement due to turbulent inflow, resulting in large variations in tensile force, which suddenly increases. 20
It is likely to cause adverse effects such as exceeding N or more.

[0041]

[Table 2]

Table 2 shows the negative pressure reducing opening 84 on the front surface.
85 shows the tensile force and the average value of the tensile forces (average of 10 times) in the case of a modified opening shape as the configuration of 85. If S1 / S ratio is 50% or more as in Table 1, the hair is easily Can be removed.

(Embodiment 3) FIG. 6 shows large negative pressure reducing openings 98, 9 of the irregular opening shape in the bathtub water passage separation forming tool 91.
9 is provided at the position farthest from the outer peripheral discharge openings 94 and 95. As the negative pressure reducing openings 96 and 97 at the front surface, in addition to φ2.7 mm * 12, the negative pressure reducing farthest Openings 98, 99 are φ2.7, φ3, φ4, φ5, φ
The average value of tensile force for each of 6 and φ7 * is shown in (Table 3).

[0044]

[Table 3]

As is clear from (Table 3), all the JIS evaluation results were clear and the average tensile force was JIS evaluated by using the large negative pressure reducing openings 98 and 99 having the irregular opening shape. About 1/2 of 20N or less
The safety factor is doubled with respect to 0N or less and 20N, and a more remarkable effect can be exhibited.

(Embodiment 4) As described in detail in the drawings of Embodiments 1 to 4, the first front surface shape of the adjoining front surface negative pressure reducing openings is used.
Exteriors 34, 36, 42, 43, 49 that form the water passages,
50, 56, 57, 65, 66, 74, 75 and 9
When the bathtub filter is attached to Nos. 4 and 95, a flat shape is provided to prevent a short circuit, thereby increasing the total area of the flat surface. Opening area S1 due to the opening, etc.
When the bathtub filter 101 shown in FIG. 7 is attached (normally used), the first water passage 94, the second
In order to more effectively perform the sealing property of the exterior part of the negative pressure reducing openings 96 and 97 on the front surface of the water passage 95, that is, the prevention of the short circuit, the bath filter 101 is opposed to the first water passage 94 and the second water passage 95. By configuring the short circuit prevention ribs 103 and 102 described above, short circuits due to suction and discharge from a plurality of negative pressure reducing openings provided on the front surfaces of the first water passage 94 and the second water passage 95 are prevented, It is possible to effectively carry out the original purpose of the bath water circulation action.

As described above, in the present embodiment, the bathtub filter was removed and used (the worst state), and the child dived into the bathtub and the hair was sucked into the outer peripheral opening of the bathtub water passage separation forming tool. Even in the state, by providing a plurality of negative pressure reducing openings in the front surface portion adjacent to the outer peripheral opening of the bath water passage separation forming tool, a plurality of negative pressure reducing openings in the front surface portion of the circulation pump are provided. Stops the action and effect that significantly reduces negative suction pressure, resulting in easy and easy removal of sucked hair with a weak pulling force. Compared with conventional products, safe and safe bath water circulation even in the worst use condition A connection device can be provided.

Although not described in detail in this embodiment, the bathtub water circulation connecting device of the present invention has a non-polar structure in which suction and discharge are possible.

[0049]

As described above, the invention according to claim 1 is
By providing a plurality of negative pressure reducing openings on the front surface adjacent to the outer peripheral opening of the bathtub water passage separation forming tool, even if foreign matter is sucked into the outer peripheral opening, the plurality of negative pressure reducing openings on the front surface are sucked in. It is possible to provide a safe and safe bath water circulation device that exhibits the effect of reducing negative pressure, can significantly improve the durability and reliability of the circulation pump, and, in the worst case, easily removes foreign substances and the like. it can.

Further, in addition to the above-mentioned claim 1, the invention according to claim 2 reduces the suction negative pressure regardless of whether the plurality of negative pressure reducing openings in the front face portion have the same shape or different shapes. This has the effect of making it possible to reduce the die cost due to the structure.

Further, in addition to the above-mentioned claim 2, the invention according to claim 3 has an S1 / S ratio of 50 with respect to the area S of the outer peripheral opening as a plurality of negative pressure reducing opening areas S1 of the front surface.
% To 150%, the suction negative pressure can be further reduced.

Further, in addition to the above first aspect, the invention according to claim 4 provides a large negative pressure reducing opening portion at a position far from the front surface portion with respect to the outer peripheral opening portion rather than the same plural shapes of the front surface portion. By this, the effect of reducing suction negative pressure can be further made effective, and since suction and discharge are close to each other, foreign matter such as hair can be prevented from approaching the bathtub water passage separation forming tool. It is possible to provide a safer and safer bathtub water circulation connection device.

Further, in addition to the above-mentioned claim 1, the invention according to claim 5 is such that the front exterior parts of the first and second water passages are formed into a flat surface, so that the plurality of openings are arranged in one row and two. Mold costs can be made even cheaper because the column configuration and wider range can be set. Further, the short circuit preventing rib provided on the bathtub filter can more reliably improve the sealing property.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a bath water circulation connection device according to a first embodiment of the present invention.

FIG. 2A is a front view of a bathtub water passage separation forming tool that constitutes the same apparatus; FIG. 2B is a partial side view showing the shape of a discharge opening provided in the forming tool.

FIG. 3 (a) is a front view of the same negative pressure reducing opening having the same shape as a rectangular opening, and FIG. 3 (b) is a front view of the same negative pressure reducing section having two rows of circular openings having the same shape.

FIG. 4 (a) is a front view of a form in which large and small circular openings are provided in the negative pressure reducing opening, and FIG. 4 (b) is a front view of a form in which circular and rectangular openings are alternately provided in the negative pressure reducing opening. FIG. 6C is a front view of a form in which a slit type opening is provided on the outer peripheral side of the negative pressure reducing opening.

FIG. 5 is a view showing a schematic test method for a hair tension test of the bath water circulation connection device according to the JIS standard of Example 2 of the present invention.

FIG. 6 is a front view of a form in which a large negative pressure reducing opening is provided near the center of the bathtub water passage separation forming tool according to the third embodiment of the present invention.

FIG. 7 is a plan view of a bathtub filter attached to the bathtub water passage separation forming tool according to the fourth embodiment of the present invention.

FIG. 8 is a configuration diagram of general construction of a conventional bathtub water circulation connection device.

FIG. 9 is an exploded perspective view of the device.

FIG. 10 (a) is a front view of a bathtub water passage separation forming tool that constitutes the same apparatus; FIG. 10 (b) is a partial front view of an elliptical opening provided on a side surface of the forming tool.

FIG. 11 is a plan view of a bathtub filter attached to the forming tool.

[Explanation of symbols]

32, 41, 48, 55, 64, 73, 91 Bathtub water passage separation forming tools 33, 44, 51, 58, 67, 76, 82 Suction opening 34 First water passages 35, 45, 52, 59, 68, 77, 83 Discharge openings 37, 46, 47, 53, 54, 60, 61, 62, 6
3, 69, 70, 71, 72, 78, 79, 80, 8
1, 84, 85, 96, 97, 98, 99 Negative pressure reducing opening

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kentaro Sahashi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Masazumi Iwanaga             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Yutaka Okano             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 3L036 AD01 AD31 AE00                 3L037 DA02 DB07

Claims (5)

[Claims] 1. A first water passage, which is attached to a through hole in a wall surface of a bathtub and is for forcibly circulating bathwater between the bathtub and a circulation pump, and which is a suction side of the bathwater. And a second water passage on the discharge side of the bath water, the first water passage having a suction opening opening to the outer periphery of the bath water passage separation forming tool. The second water passage has a discharge opening opening to the outer circumference of the bathtub water passage separation forming tool, and the bathtub is adjacent to the suction opening of the first water passage and the discharge opening of the second water passage. A bath water circulation connecting device comprising a plurality of negative pressure reducing openings smaller than the suction opening and the discharge opening in a part of the water passage separation forming tool. 2. The bath water circulation connection device according to claim 1, wherein the negative pressure reducing openings have the same or different shapes. 3. The area S1 of the negative pressure reducing opening is 60 to 150% of the opening area S of the suction opening and the discharge opening.
The bathtub water circulation connection device according to claim 1 or 2. 4. A plurality of irregularly shaped negative pressure reducing openings, each of which has a large size, is arranged at a position farthest from the positions of the suction opening and the discharge opening. The bathtub water circulation connection device according to any one of claims. 5. The bathtub circulation according to claim 1, wherein a surface shape of the negative pressure reducing opening is a flat shape in order to prevent a short circuit when the bathtub filter is attached. Water connection device.