CN110857574A

CN110857574A - Drainage bent pipe

Info

Publication number: CN110857574A
Application number: CN201910774241.4A
Authority: CN
Inventors: 山本正树
Original assignee: Bridgestone Corp
Current assignee: Bridgestone Corp
Priority date: 2018-08-22
Filing date: 2019-08-21
Publication date: 2020-03-03
Also published as: JP7167401B2; JP2020029708A; TW202024436A

Abstract

The invention provides a drain bend pipe which can realize further low floor. The 1 st drain trap (21) has: a bent pipe main body part (21B) which is substantially tubular, is arranged at the downstream side of a drainage part (41) arranged at the bottom of the water using appliance, and is provided with a part extending towards the lower side and a part extending towards the horizontal direction from the lower end of the part extending towards the lower side; and a lower protruding portion (23) provided on the upper wall inside the bent pipe main body portion (21B), the lower protruding portion (23) protruding downward such that the tip end portion (23A) thereof is closer to the bottom wall (21BB) of the bent pipe main body portion (21B) than the other portions.

Description

Drainage bent pipe

Technical Field

The present disclosure relates to a drain trap.

Background

Patent document 1 discloses a drain structure, a drain structure of a shower room, and a drain structure of a waterproof mount for a washing machine (japanese: washer waterproof パン). In this drain structure, the floor surface of the shower is disposed at a position lower than the upper end of the drain trap. This enables the shower to be made low in floor area.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-59654

Disclosure of Invention

Problems to be solved by the invention

In order to achieve further low floor height, it is considered to apply a siphon drain pipe having a smaller diameter than that of a conventional gradient pipe, but even if a drain trap of a conventional structure is applied to a siphon drain pipe, a certain height is required to accumulate water seal in the drain trap, and it is necessary to secure an underfloor space according to the height. Therefore, it is difficult to realize further low floor.

The invention aims to provide a drain trap capable of realizing further low floor.

Means for solving the problems

The drain trap pipe according to claim 1 includes: a substantially tubular elbow main body portion provided downstream of a drain portion provided at a bottom of the water using appliance and having a portion extending downward and a portion extending horizontally from a lower end of the portion extending downward; and a convex portion provided on an upper wall in the bent pipe main body, the convex portion protruding downward such that a tip end portion thereof is closer to a bottom wall of the bent pipe main body than other portions.

According to the drain trap of claim 1, the drain trap has a trap main body portion and a convex portion. The elbow pipe main body is formed in a substantially tubular shape, is provided on the downstream side of the drain portion provided on the bottom of the water using appliance, and has a portion extending downward and a portion extending horizontally from the lower end of the portion extending downward. The convex portion is provided on an upper wall in the elbow main body, and a tip end portion of the convex portion protrudes downward so as to be closer to a bottom wall of the elbow main body than other portions. Therefore, the water seal accumulated in the drain trap is not easily broken by the amount of the protrusion protruding downward. That is, since the water seal can be effectively accumulated in the interior of the drain trap in advance by the simple shape of the drain trap itself, the structure of the drain trap can be simplified, and the space required for installing the drain trap can be reduced. Further, the convex portion protrudes so as to be close to the bottom wall. That is, the bottom wall of the elbow main body is suppressed from protruding downward. Therefore, the dimension of the elbow pipe main body itself in the vertical direction can be controlled, and therefore, the underfloor space required for installation can be reduced.

A drain trap according to claim 2 is the drain trap according to claim 1, further comprising an overflow portion provided at a portion of the bottom wall in the trap body portion downstream of the convex portion, the overflow portion projecting upward so that a tip end portion thereof is closer to the upper wall of the trap body portion than other portions, and being located higher than the tip end portion of the convex portion.

According to the drain trap of claim 2, the overflow portion is provided at a portion of the bottom wall in the trap body portion on the downstream side of the convex portion, and the overflow portion protrudes upward so that the tip end portion thereof is closer to the upper wall of the trap body portion than the other portions, and is located higher than the tip end portion of the convex portion. Therefore, the drain trap can accumulate the water seal at a portion located on the lower side than the overflow portion in advance, and the water seal is less likely to be broken by the amount by which the convex portion protrudes downward. That is, since the water seal can be effectively accumulated in the interior of the drain trap in advance by the simple shape of the drain trap itself, the structure of the drain trap can be simplified, and the space required for installing the drain trap can be reduced. Further, the overflow portion protrudes so as to be close to the upper wall. That is, the upper wall of the elbow pipe main body is suppressed from protruding upward. Therefore, the dimension of the elbow pipe main body itself in the vertical direction can be controlled, and therefore, the underfloor space required for installation can be further reduced.

In the drain trap pipe according to claim 3, in addition to the drain trap pipe according to claim 2, an inclined portion that extends obliquely upward with respect to a bottom wall of a portion of the trap pipe main body that extends in the horizontal direction is provided between the convex portion and the overflow portion in the trap pipe main body.

According to the drain trap of claim 3, since the inclined portion extending obliquely upward with respect to the bottom wall of the portion of the trap main body extending in the horizontal direction is provided between the convex portion and the overflow portion in the trap main body, the water seal reservoir in which the water seal is accumulated is formed including the inclined portion. Accordingly, the water seal amount can be ensured without increasing the size of the drain trap, and therefore, the space required for installing the drain trap can be further reduced.

The drain trap according to claim 4 is the drain trap according to claim 2 or 3, wherein a width of a flow path between a distal end portion of the overflow portion and an upper wall of the trap main body portion is formed larger than a width of the drain portion in the trap main body portion.

According to the drain trap of claim 4, the width of the flow path between the top end of the overflow section and the upper wall in the trap main body is formed larger than the width of the drain section, and thus the flow rate can be secured even at the portion where the overflow section is provided. Therefore, the water can be smoothly discharged.

The drain trap according to claim 5 is the drain trap according to any one of claims 2 to 4, wherein a vent pipe is connected substantially horizontally to the trap body portion on a downstream side of the overflow portion.

According to the drain trap of claim 5, since the vent pipe is connected to the trap body portion at a position downstream of the overflow portion, the vent pipe is connected to the drain trap at a position farther from the water seal reservoir. That is, the vent pipe can be connected to the drain trap at a place other than the place where the water seal is stored in the underfloor space and where there is a space margin. Further, the breather pipe is connected substantially horizontally, and therefore, the height of the underfloor space can be further reduced.

The drain trap according to claim 6 is the drain trap according to any one of claims 1 to 5, wherein a width of a flow path between a distal end portion of the convex portion and a bottom wall of the trap main body portion is formed larger than a width of the drain portion in the trap main body portion.

According to the drain trap of claim 6, the width of the flow path between the distal end of the convex portion and the bottom wall in the trap main body portion is formed larger than the width of the drain portion, and thus the flow rate can be secured even at the portion where the convex portion is provided. Therefore, the water can be smoothly discharged.

The drain trap according to claim 7 is the drain trap according to any one of claims 1 to 6, wherein the projection of the projection toward the lower side is formed so as to gradually increase from the upstream side toward the downstream side in the trap main body portion.

According to the drain trap of claim 7, since the amount of projection of the convex portion toward the lower side is set to be gradually larger as going from the upstream side to the downstream side in the trap main body portion, the drain water colliding with the convex portion can be smoothly guided to the distal end portion of the convex portion when the drain water flows. That is, resistance at the time of drainage can be suppressed.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the drain trap pipe of the present invention, a further reduction in floor area can be achieved.

Drawings

Fig. 1 is a sectional view showing an outline of a siphon drainage system according to embodiment 1.

Fig. 2 is a schematic perspective view showing the drainage structure of embodiment 1.

Fig. 3 is a sectional view showing an initial stage when water is drained from a bathtub in the drain structure of embodiment 1.

Fig. 4 is a sectional view showing a state of water drainage after generation of siphon force.

Fig. 5 is a sectional view showing a drainage state of water from a shower in the drainage structure of embodiment 1.

Fig. 6 is a sectional view of a 1 st drain trap pipe showing a drain structure of the 1 st embodiment.

Fig. 7 is a plan view of a 1 st drain trap pipe showing the drain structure of the 1 st embodiment.

Fig. 8 is an exploded perspective view showing a structure in which a skirt of a bathtub is detachable in the drain structure according to embodiment 1.

Fig. 9 is a sectional view of a 1 st drain trap pipe showing a drain structure according to embodiment 2.

Fig. 10 is a plan view of a 1 st drain trap pipe showing a drain structure according to embodiment 2.

Fig. 11 is a perspective view schematically showing the drainage structure of embodiment 3.

Fig. 12 is a perspective view schematically showing a drainage structure according to embodiment 4.

Fig. 13 is a perspective view schematically showing the drainage structure of embodiment 5.

Fig. 14 is a perspective view schematically showing the drainage structure of reference example 1.

Fig. 15 is a perspective view schematically showing the drainage structure of reference example 2.

Fig. 16 is a sectional view showing the drainage structure of embodiment 6.

Fig. 17 is a sectional view showing a water discharge structure according to embodiment 7.

Fig. 18 is a sectional view of a 1 st drain trap pipe showing a drain structure according to embodiment 8.

Fig. 19 is a sectional view of a 1 st drain trap pipe showing a drain structure according to embodiment 9.

Description of the reference numerals

11. Bathtub (water-using appliance); 12. shower (water-using utensil); 18. 1 st bypass pipe (snorkel); 21. 1 st drain trap (drain trap); 21B, a bent pipe main body part; 21BA, upper wall; 21BB, a bottom wall; 21CB, a part extending in the horizontal direction; 21CC, a part extending to the lower side; 21D, 2 nd flow path part (inclined part); 22. 2, a drainage bent pipe; 23. a lower protruding portion (convex portion); 23A, a tip portion; 27. an upper protruding portion (overflow portion); 27A, a tip portion; 41. a water discharge section; 64. a protrusion; 132ED, 1 st elbow wall (overflow); 132CD, No. 2 elbow wall (convex).

Detailed Description

Hereinafter, embodiments for carrying out the present invention will be described based on the drawings.

[ embodiment 1]

In fig. 1, a siphon drainage system 10 of the present embodiment has a drainage stand pipe 14 and a drainage structure 16.

The drainage pipe 14 penetrates through a through hole 25 of a floor 24 of the building 15. The vertical drain pipe 14 is provided with a drain joint 28 that connects

vertical pipes

31B and 32B described later, and is configured to join drain from the vertical drain pipe 14 at the upper portion and drain from a water-using appliance such as a bathtub 11 and a shower 12 described later. In the drawings used in the following description, the pipe joint and the like, the pipes, the structure of the connection portion of the pipes, the direction of the pipes, and the like are appropriately omitted and simplified for easy understanding of the pipe structure.

(drainage structure)

The drain structure 16 includes a bathtub 11 as an example of a water-using appliance, a shower 12 as an example of a water-using appliance, a 1 st drain trap 21 and a 2 nd drain trap 22 as drain traps, a 1 st bypass pipe 18 as a vent pipe, a 1 st siphon drain pipe 31, and a 2 nd siphon drain pipe 32.

The bathtub 11 is an example of the 1 st water appliance used while storing water 20, and the drain is collected drain by storing water and then draining. The shower 12 is an example of the 2 nd water use utensil, and the drain is continuous drain without water storage. The bathtub 11 and the shower 12 are adjacent to each other with a gap S therebetween. The bathtub 11 and the shower 12 may be integrated with each other as shown in the drawing, or may be independent from each other.

The 1 st and 2

nd drain elbows

21 and 22 are so-called water-sealed elbows for preventing reverse flow of foul odors, gases, and the like. The 1 st drain trap 21 is provided in the drain portion 41 of the bathtub 11. The 2 nd drain trap 22 is provided in the drain portion 42 of the shower 12.

As shown in fig. 2, the 1 st bypass pipe 18 is a pipe body that connects a drain pipe 51, which is an example of a downstream side portion of the 1 st drain trap 21, and a drain pipe 52, which is an example of a downstream side portion of the 2 nd drain trap 22. The 1 st bypass pipe 18 is provided in a space S (see fig. 1) between the bathtub 11 and the shower 12, and is provided so as not to be visible to a user in normal use. By providing the 1 st bypass pipe 18 in the gap S, the space can be effectively used. The 1 st bypass pipe 18 may be provided at another place (not shown) such as between a bathroom and a wall of a building.

As shown in fig. 3, at least a part of the 1 st bypass pipe 18, for example, the uppermost portion 18H, is located above both the 1 st drain trap 21 and the 2 nd drain trap 22. Here, "above both the 1 st drain trap 21 and the 2 nd drain trap 22" means above the top surface 21A of the 1 st drain trap 21 and above the top surface 22A of the 2 nd drain trap 22. The 1 st bypass pipe 18 is formed in an inverted U shape, for example, and includes a 1 st drain trap 21-side vertical pipe portion 18A, a 2 nd drain trap 22-side vertical pipe portion 18B, and a connecting portion 18D between the vertical pipe portion 18A and the vertical pipe portion 18B. The connecting portion 18D extends, for example, in the horizontal direction. The uppermost portion 18H refers to a bottom surface of the pipe in the connection portion 18D, which is located above both the 1 st drain trap 21 and the 2 nd drain trap 22. When the height of the bottom surface of the pipe line in the connection portion 18D is not constant, the highest position is the uppermost portion 18H. Further, the uppermost portion 18H is given as an example of at least a part of the line of the 1 st bypass pipe 18, but a portion other than the uppermost portion 18H may be located above both the 1 st drain trap 21 and the 2 nd drain trap 22.

The drain pipe 51 includes an upper cross pipe portion 51A extending in the lateral direction from the first drain trap 21 and merging with the vertical pipe portion 18A of the 1 st bypass pipe 18, a vertical pipe portion 51B extending downward from the lower end of the vertical pipe portion 18A, and a lower cross pipe portion 51C extending in the lateral direction from the lower end of the vertical pipe portion 51B. Similarly, the drain pipe 52 includes an upper horizontal pipe portion 52A extending in the lateral direction from the second drain trap 22 and merging with the vertical pipe portion 18B of the first bypass pipe 18, a vertical pipe portion 52B extending downward from the lower end of the vertical pipe portion 18B, and a lower horizontal pipe portion 52C extending in the lateral direction from the lower end of the vertical pipe portion 52B. The configuration of the

drain pipes

51 and 52 is not limited to this, and may be any configuration as long as water can be drained from the 1 st drain trap 21 and the 2 nd drain trap 22, respectively.

The 1 st bypass pipe 18 is provided with an intake valve 30. The intake valve 30 is a member for allowing air from outside to pass through the 1 st bypass pipe 18 and preventing drain water and air from passing through the 1 st bypass pipe 18 to the outside. The intake valve 30 is provided at the upper end of the extension portion 18C of the vertical pipe portion 18A, for example. When the extension portion 18C is included, it can be said that the 1 st bypass pipe 18 is formed in the shape of a character of mirror image in which the letter h is reversed. When the 1 st bypass pipe 18 is viewed from the opposite side, the 1 st bypass pipe 18 has an h-shape. The suction valve 30 may be provided at the connection portion 18D of the 1 st bypass pipe 18. The extension portion 18C and the intake valve 30 may be provided above the vertical pipe portion 18B.

It is desirable that the uppermost portion 18H of the piping in the 1 st bypass pipe 18 has a height position that is the same as or higher than the height position of the standard head H of the water 20 stored in the bathtub 11. The water head H is referenced to, for example, the bottom of the bathtub 11. The standard water head H is an amount of hot water corresponding to the amount of hot water stored in the bathtub 11 when a person takes a bath, for example, an amount of hot water corresponding to an amount of hot water that does not overflow from the bathtub 11 when a person sits down in the bathtub 11. The uppermost portion 18H is the maximum height at which overflow does not occur between the

vertical pipe portions

18A and 18B in the 1 st bypass pipe 18, and corresponds to the height of the bottom surface of the connection portion 18D.

In fig. 2, the 1 st siphon drain pipe 31 is connected to the 1 st drain trap 21 and the downstream side of the 1 st bypass pipe 18. Further, the 2 nd siphon drain pipe 32 is connected to the 2 nd drain trap 22 and the downstream side of the 1 st bypass pipe 18.

Specifically, the 1 st siphon drain pipe 31 is connected to the end of the down pipe portion 51C of the drain pipe 51. In fig. 1, the 1 st siphon drain pipe 31 includes a lateral pipe 31A for flowing drain in a lateral direction and a vertical pipe 31B connected to the vertical drain pipe 14 and for flowing drain from the lateral pipe 31A downward. The 2 nd siphon drain pipe 32 includes a lateral pipe 32A for flowing the drain water in the lateral direction and a vertical pipe 32B connected to the vertical drain pipe 14 and for flowing the drain water from the lateral pipe 32A in the downward direction. The lower end of the standpipe 31B and the lower end of the standpipe 32B are connected to the drain connector 28. The 1 st siphon drain 31 and the 2 nd siphon drain 32 are arranged in parallel on the back side of the 2 nd siphon drain 32.

As shown in fig. 6, the 1 st drain elbow 21 has an elbow main body 21B provided on the downstream side of the drain portion 41 and formed in a tubular shape. The elbow main body portion 21B has a 1 st flow path portion 21C, a 2 nd flow path portion 21D as an inclined portion, a 3 rd flow path portion 21E, and a 4 th flow path portion 21F. The 1 st flow path portion 21C is provided at a position corresponding to the drain portion 41, that is, at a lower side of the drain portion 41, and includes a portion 21CC extending downward from the drain portion 41 and a portion 21CB extending in a horizontal direction from a lower end of the portion 21CC extending downward. That is, the bent pipe main body 21B is bent in the horizontal direction at a position corresponding to the drain portion 41, that is, at a position below the drain portion 41 and in the middle of the flow path extending downward. A portion 21CB of the 1 st flow path portion 21C extending in the horizontal direction is placed on the floor 24 (see fig. 1). That is, the 1 st flow path portion 21C is set to a range from the end portion 21CA on the bathtub 11 side in the 1 st drain trap 21 to a boundary B1 between the horizontally extending portion 21CB and the 2 nd flow path portion 21D.

The 2 nd flow path part 21D is provided adjacent to the 1 st flow path part 21C on the downstream side of the 1 st flow path part 21C, and extends obliquely upward with respect to the downstream end part (the part 21CB extending in the horizontal direction) of the 1 st flow path part 21C. That is, the 2 nd flow path unit 21D is set to a range from the boundary B1 to the boundary B2 between the 2 nd flow path unit 21D and the 3 rd flow path unit 21E.

The 3 rd flow path part 21E is provided adjacent to the 2 nd flow path part 21D on the downstream side of the 2 nd flow path part 21D, and extends from the downstream end of the 2 nd flow path part 21D toward the obliquely lower side, that is, toward the floor slab 24 side. That is, the 3 rd flow path part 21E is set to a range from the boundary B2 to the boundary B3 between the 3 rd flow path part 21E and the 4 th flow path part 21F.

The 4 th flow path part 21F is provided adjacent to the 3 rd flow path part 21E on the downstream side of the 3 rd flow path part 21E, extends in the horizontal direction from the downstream end of the 3 rd flow path part 21E, and is placed on the floor 24 (see fig. 1). That is, the 4 th flow path portion 21F is set to a range from the boundary B3 to the end to which the 1 st siphon drain pipe 31 is connected. The lower end of the 2 nd flow path part 21D is at the same height as the 4 th flow path part 21F, and is placed on the floor slab 24. In other words, the 1 st drain trap 21 has a structure in which the drain pipe 51 is integrally provided. The lower end of the 2 nd flow path part 21D and the 4 th flow path part 21F are at the same height, but the present invention is not limited thereto, and when the lower end of the 2 nd flow path part 21D and the 4 th flow path part 21F are at different heights, at least the 4 th flow path part 21F may be placed on the floor 24.

The upper side (upstream side) of the opening of the 1 st drain trap 21 on the bathtub 11 side is expanded in diameter relative to the lower side (downstream side). In other words, the opening of the 1 st drain trap 21 on the bathtub 11 side projects radially outward with respect to the portion other than the opening.

The bent tube main body portion 21B is provided with a lower protruding portion 23 as a convex portion. Specifically, the lower protruding portion 21 is formed by the side wall of the portion 21CC extending downward of the 1 st flow path portion 21C and the upper wall 21BA side of the portion 21CB extending horizontally, and the lower protruding portion 23 protrudes downward along the side wall of the portion 21CC extending downward so that the tip end portion 23A thereof is close to the bottom wall 21BB of the 1 st flow path portion 21C of the elbow main body portion 21B. That is, the tip portion 23A faces the bottom wall 21 BB. On the other hand, the bottom wall 21BB of the 1 st flow path portion 21C extends horizontally, and therefore, in other words, the height of the flow path at the portion where the lower protruding portion 23 is provided is lower than the height of the flow path at other portions.

An upper protruding portion 27 as an overflow portion is provided on the downstream side of the lower protruding portion 23 in the 1 st drain trap 21. The upper protruding portion 27 is provided at a boundary B2 between the 2 nd flow path portion 21D and the 3 rd flow path portion 21E in the bottom wall 21BB of the elbow main body portion 21B, and the upper protruding portion 27 protrudes upward so that the tip end portion 27A thereof is closer to the upper wall 21BA and is located higher than the tip end portion 23A of the lower protruding portion 23. That is, the tip portion 27A faces the upper wall 21 BA. On the other hand, the upper wall 21BA of the 2 nd flow path portion 21D at the portion corresponding to the upper protruding portion 27 extends horizontally, and therefore, in other words, the height of the flow path at the portion where the upper protruding portion 27 is provided is higher than the height of the flow path at the other portion.

The upper protrusion 27 is provided at a vertex in the bottom wall 21BB of the 2 nd flow path unit 21D extending obliquely upward with respect to the portion 21CB of the 1 st flow path unit 21C extending in the horizontal direction. In other words, the 2 nd flow path portion 21D, which is an inclined portion extending obliquely upward with respect to the bottom wall 21BB of the portion 21CB of the 1 st flow path portion 21C extending in the horizontal direction, is provided between the lower protruding portion 23 and the upper protruding portion 27. A water seal reservoir 21G is formed in a portion of the 1 st flow path portion 21C and the 2 nd flow path portion 21D of the elbow main body 21B that is lower than the upper protruding portion 27. The amount of projection of each of the lower projecting portion 23 and the upper projecting portion 27 is set to a level that can ensure a required water seal.

As shown in fig. 7, the 1 st drain trap 21 has widened portions 29 formed at portions corresponding to the lower protruding portion 23 and the upper protruding portion 27, respectively. The widened portion 29 is a portion that is widened radially outward of the 1 st drain elbow 21 in plan view, and the width of the flow path between the lower protruding portion 23 and the bottom wall 21BB and the width of the flow path between the upper protruding portion 27 and the upper wall 21BA (see fig. 6) are formed larger than the width (diameter) of the drain portion 41 (see fig. 6). It is preferable that the cross-sectional area of the flow path between the lower protruding portion 23 and the bottom wall 21BB and the cross-sectional area of the flow path between the upper protruding portion 27 and the upper wall 21BA (see fig. 6) be equal to or larger than the cross-sectional area of the drain portion 41 (see fig. 6).

As shown in fig. 6, the 1 st bypass pipe 18 is horizontally connected to a portion of the 3 rd flow path portion 21E of the elbow main body portion 21B above the water seal reservoir 21G. Specifically, the 1 st bypass pipe 18 is connected to the 3 rd flow path portion 21E in a state of extending horizontally from the upper side toward the downstream side of the 1 st drain trap 21.

As shown in fig. 8, in the drain structure 16, a skirt 40 constituting a side surface of the shower 12 on the bathtub 11 side may be detachably attached. In this case, by removing the skirt 40, the drain structure 16 can be easily maintained.

(action and Effect of the embodiment)

The present embodiment is configured as described above, and its operation will be described below. In fig. 3, in the drain structure 16 of the present embodiment, since the drain from the bathtub 11 is collected and drained after storing water, much drain is discharged at one time as compared with the drain from the shower 12. The drain from the bathtub 11 passes through the upper horizontal pipe portion 51A, the vertical pipe portion 51B, and the lower horizontal pipe portion 51C of the drain pipe 51 via the 1 st drain trap 21, and flows toward the 1 st siphon drain pipe 31 (in the direction of the arrow a). Before the siphon force is generated in the 1 st siphon drain pipe 31, the remaining drain water flows into the 1 st bypass pipe 18 (arrow B direction). The air in the 1 st bypass pipe 18 is pushed out toward the 2 nd drain trap 22 (in the direction of arrow C) with the inflow of drain.

The 1 st bypass pipe 18 is formed in an inverted U shape, and the uppermost portion 18H of the pipe is located above both the 1 st drain trap 21 and the 2 nd drain trap 22, so that the drain water flowing into the 1 st bypass pipe 18 is less likely to flow toward the 2 nd drain trap 22. In particular, when the height position of the uppermost portion 18H of the pipeline in the 1 st bypass pipe 18 is the same as the height position of the standard water head H of the water stored in the bathtub 11, overflow from the vertical pipe portion 18A to the vertical pipe portion 18B is less likely to occur. In addition, overflow may be generated to such an extent that the water seal of the 2 nd drain trap 22 is not broken.

In fig. 4, when the siphon force is generated in the 1 st siphon drain pipe 31, the drain from the bathtub 11 and the drain flowing into the 1 st bypass pipe 18 are quickly discharged through the 1 st siphon drain pipe 31 (arrow a direction), and the water level of the bathtub 11 is lowered (arrow D direction). At this time, the self-priming valve 30 introduces the outside air (in the direction of arrow E) into the 1 st bypass pipe 18, and thus, the negative pressure is suppressed from acting on the 2 nd drain trap 22 side. Therefore, the water seal of the 2 nd drain trap 22 is not broken.

Thus, according to the drain structure 16, the accumulated drain from the bathtub 11 can be prevented from overflowing into the shower 12 without using a temporary storage tank as in the conventional case.

On the other hand, in fig. 5, the drain from the shower 12 is continuous drain without water storage. The drain from the shower 12 passes through the 2 nd drain trap 22 from the upper cross pipe portion 52A, the vertical pipe portion 52B, and the lower cross pipe portion 52C of the drain pipe 52, and flows to the 2 nd siphon drain pipe 32 (in the direction of arrow F). The air in the line of the 1 st bypass pipe 18 is pushed out (in the direction of arrow G) toward the 1 st drain trap 21 via the 1 st bypass pipe 18, and therefore, the water is smoothly drained from the shower 12. In the case of continuous drainage, there is almost no water head, and therefore, the drainage does not flow into the longitudinal pipe portion 18B of the 1 st bypass pipe 18. When the siphon force is generated at the 2 nd siphon drain pipe 32, the drain water from the shower 12 is rapidly discharged via the 2 nd siphon drain pipe 32 (arrow F direction). At this time, if the water is discharged only from the shower 12, negative pressure is hardly generated in the 1 st bypass pipe 18, and when negative pressure is generated in the 1 st bypass pipe 18 such as when the water is discharged simultaneously with the bathtub 11, the water seal of the 1 st drain trap 21 and the water seal of the 2 nd drain trap 22 are not broken because the external air is introduced from the air suction valve 30.

In fig. 1, in the siphon drainage system 10 according to the present embodiment, the drainage from the bathtub 11 can be made to flow to the drainage stand pipe 14 through the lateral pipe 31A and the vertical pipe 31B included in the 1 st siphon drainage pipe 31. In the siphon drain system 10, the drain water from the shower 12 can be made to flow to the drain stand pipe 14 through the cross pipe 32A and the stand pipe 32B included in the 2 nd siphon drain pipe 32.

As shown in fig. 6, the 1 st drain trap 21 includes a trap body 21B, a lower protrusion 23, and an upper protrusion 27. The elbow main body 21B is formed in a substantially tubular shape, is provided on the downstream side of the drain portion 41 provided at the bottom of the bathtub 11, and has a portion 21CC extending downward and a portion 21CB extending horizontally from the lower end of the portion 21CC extending downward. The lower protruding portion 23 is provided on the upper wall 21BA in the elbow main body 21B, and the lower protruding portion 23 protrudes downward such that the distal end portion 23A is closer to the bottom wall 21BB of the elbow main body 21B than the other portions. The upper protruding portion 27 is provided at a portion of the bottom wall 21BB in the elbow main body 21B on the downstream side of the lower protruding portion 23, and the upper protruding portion 27 protrudes upward so that the tip end portion 27A is closer to the upper wall 21BA of the elbow main body 21B than the other portions, and is located higher than the tip end portion 23A of the lower protruding portion 23. Therefore, the 1 st drain trap 21 can accumulate the water seal at a portion located on the lower side than the upper protruding portion 27 in advance, and the water seal is less likely to be broken by the amount by which the lower protruding portion 23 protrudes downward. That is, since the water seal can be effectively accumulated in the 1 st drain trap 21 in advance by the simple shape of the 1 st drain trap 21 itself, the structure of the 1 st drain trap 21 can be simplified, and the space required for installing the 1 st drain trap 21 can be reduced. Further, the lower protruding portion 23 protrudes so as to be close to the bottom wall 21 BB. That is, the bottom wall 21BB of the elbow main body 21B is suppressed from protruding downward. The upper protruding portion 27 protrudes so as to be close to the upper wall 21 BA. That is, the upper wall 21BA of the elbow main body 21B is suppressed from protruding upward. Therefore, the dimension of the elbow main body portion 21B itself in the vertical direction can be controlled, and therefore, the underfloor space required for installation can be reduced. This enables further reduction in floor area.

Further, a 2 nd flow path portion 21D extending obliquely upward with respect to the bottom wall 21BB in the portion 21CB extending in the horizontal direction of the elbow main body 21B is provided between the lower protruding portion 23 and the upper protruding portion 27 in the elbow main body 21B, and therefore a water seal reservoir 21G for storing water inside is formed including the 2 nd flow path portion 21D. This can ensure the water-seal amount without increasing the size of the 1 st drain trap 21, and therefore, the space required for installing the 1 st drain trap 21 can be further reduced.

Further, the cross-sectional area of the flow path between the distal end portion 23A of the lower protruding portion 23 and the bottom wall 21BB in the bent tube main body portion 21B is preferably formed to be equal to the cross-sectional area of the drain portion 41 or larger than the cross-sectional area of the drain portion 41, whereby the flow rate can be secured even at the portion where the lower protruding portion 23 is provided. Therefore, the water can be smoothly discharged.

Further, the cross-sectional area of the flow path between the tip end portion 27A of the upper protruding portion 27 and the upper wall 21BA in the bent pipe main body portion 21B is preferably formed to be equal to the cross-sectional area of the drain portion 41 or larger than the cross-sectional area of the drain portion 41, whereby the flow rate can be secured even at the portion where the upper protruding portion 27 is provided. Therefore, the water can be smoothly discharged.

As described above, according to the drain structure 16 and siphon drain system 10 of the present embodiment, a temporary storage tank as in the conventional art is not required, and therefore, the installation location of the bathtub 11 and the like for performing the accumulated water drain can be further reduced in floor space.

Further, the lower side projection 23 is applied to the 1 st drain trap 21, but the present invention is not limited thereto, and the 2 nd drain trap 22 may have the same configuration as the 1 st drain trap 21.

Further, the 1 st drain trap 21 is provided with the upper protruding portion 27, but the present invention is not limited to this, and may be configured such that only the lower protruding portion 23 is provided without providing the upper protruding portion 27.

[ 2 nd embodiment ]

As shown in fig. 9, the drain structure 60 of the present embodiment is configured such that a projection 64, which is a convex portion provided inside the bent pipe main body portion 62A of the 1 st drain bent pipe 62, is formed as compared with the 1 st embodiment, and the amount of projection of the projection 64 on the downward side is formed to gradually increase from the upstream side to the downstream side of the 1 st drain bent pipe 62. That is, the protrusion 64 is formed by a side wall of the portion 21CC extending downward of the 1 st flow path portion 21C and an upper wall 21BA of the portion 21CB extending horizontally, and has a curved surface 64A in which the amount of protrusion toward the bottom wall 21BB side increases as going from the upstream side to the downstream side of the 1 st drain trap 62.

As shown in fig. 10, a widened portion 65 is formed in the 1 st drain trap 62 at a position between the projection 64 and the upper projection 27. The widened portion 65 is a portion that is substantially uniformly expanded radially outward of the 1 st drain trap 62 between the protruding portion 64 and the upper protruding portion 27 in plan view, and the width of the flow path between the protruding portion 64 and the bottom wall 21BB and the width of the flow path between the upper protruding portion 27 and the upper wall 21BA are formed larger than the width (diameter) of the drain portion 41 (see fig. 9). It is preferable that the cross-sectional area of the flow path between the protrusion 64 and the bottom wall 21BB and the cross-sectional area of the flow path between the upper protrusion 27 and the upper wall 21BA are the same as or larger than the cross-sectional area of the drain 41 (see fig. 9).

In the present embodiment, since the basic configuration is the same as that of embodiment 1, the same operational effects as those of embodiment 1 can be obtained. Further, the projecting portion 64 is set so that the projecting amount thereof gradually increases from the upstream side to the downstream side in the 1 st drain trap 62, and therefore, the drain water colliding with the projecting portion 64 can be smoothly guided to the distal end portion 64B of the projecting portion 64 when the drain water flows. That is, resistance at the time of drainage can be suppressed.

Further, the widened portion 65 is formed to be substantially constant in diameter outward in the radial direction of the 1 st drain trap 62 between the protruding portion 64 and the upper protruding portion 27 in plan view, and therefore the amount of water seal in the 1 st drain trap 62 can be increased. This can smooth the flow of the drain water.

Since the other portions are the same as those in embodiment 1, the same reference numerals are given to the same portions in the drawings, and the description thereof is omitted.

[ embodiment 3 ]

In fig. 11, the drain structure 26 of the present embodiment has

auxiliary chambers

71, 72 in at least one of the downstream side portion of the 1 st drain trap 21 and the downstream side portion of the 2 nd drain trap 22, for example, both of them. The auxiliary chamber 71 is provided at a downstream side portion of the 1 st drain trap 21. The auxiliary chamber 72 is provided at a downstream side portion of the 2 nd drain trap 22.

The

auxiliary chambers

71 and 72 are, for example, large-diameter portions (inner diameter-enlarged portions) provided in the

drain pipes

51 and 52, respectively. The height dimensions of the

auxiliary chambers

71 and 72 are set smaller than those of conventional temporary storage tanks, and can be set to a size that can be disposed in a space required for disposing the 1 st drain trap 21, the 2 nd drain trap 22, and the

drain pipes

51 and 52. Thus, an extra underfloor space is not required for providing the

auxiliary chambers

71, 72.

In the illustrated example, both the

auxiliary chambers

71 and 72 are disposed upstream of the 1 st bypass pipe 18, but either one of the

auxiliary chambers

71 and 72 or both of the

auxiliary chambers

71 and 72 may be disposed downstream of the 1 st bypass pipe 18.

In the drain structure 26, the

auxiliary chambers

71 and 72 can receive the surplus drain exceeding the capacity of the 1 st bypass pipe 18. When the shower 12 (fig. 1) uses water drawn up from the bathtub 11 (fig. 1), a larger amount of water than usual is discharged from the shower 12. In this case, the retention of the drain water from the shower 12 can be suppressed by receiving the drain water by the

auxiliary chambers

71, 72. In addition, a larger amount of accumulated drain from the bathtub 11 can be dealt with.

[ 4 th embodiment ]

In fig. 12, in the drain structure 36 of the present embodiment, a breather pipe 74 is connected to the 1 st bypass pipe 18 in place of the suction valve 30 (fig. 2). The air duct 74 extends, for example, to the outside of a building, and its end 74A is open to the atmosphere.

In this drainage structure 36, the air vent pipe 74 is provided instead of the air suction valve 30 (fig. 2), and therefore, an arrangement space for the air suction valve 30 is not required.

When the siphon suction force is generated in the 1 st siphon drain pipe 31, the external air is introduced from the vent pipe 74 into the 1 st bypass pipe 18, and therefore, the water seal of the 2 nd drain trap 22 is not broken. When the siphon suction force is generated in the 2 nd siphon drain pipe 32, the outside air is also introduced from the vent pipe 74 into the 1 st bypass pipe 18, and therefore the water seal of the 1 st drain trap 21 is not broken.

[ 5 th embodiment ]

In fig. 13, the drain structure 46 of the present embodiment includes

other drain elbows

83 and 84, siphon

drains

93 and 94,

independent air ducts

103 and 104, a header 80, and a merged air duct 90.

The other drain trap 83 is provided to a drain portion (not shown) of a washing machine as an example of another water-using device. The other drain trap 84 is provided to a wash stand as an example of another water-using appliance. The

other drain elbows

83 and 84 are so-called water-sealed elbows for preventing backflow of foul odors, gases, and the like.

A drain pipe 113 is connected to the downstream side of the other drain trap 83. The siphon drain pipe 93 is connected to the downstream side of the drain pipe 113. A drain pipe 114 is connected to the downstream side of the other drain elbow 84. Siphon drain 94 is connected to the downstream side of drain 114.

One end of the independent breather pipe 103 is connected to a downstream side portion (the drain pipe 113) of the other drain trap 83. One end of the independent vent pipe 104 is connected to a downstream side portion (a drain pipe 114) of the other drain trap 84. The other ends of the

independent air pipes

103, 104 are connected to the header 80, respectively.

The manifold 80 is a pipe joint to which the breather pipe 74 and the

independent breather pipes

103 and 104 are connected. The confluent vent 90 is connected to the header 80 and is open to the atmosphere. Specifically, the merged flue pipe 90 extends to the outside of the building, for example, and the end 90A thereof is open to the atmosphere.

In this drainage structure 46, the breather pipe 74 and the

independent breather pipes

103 and 104 are provided instead of the intake valve 30 (fig. 2), and therefore, an arrangement space for the intake valve 30 is not required. The vent pipe 74 and the

independent vent pipes

103 and 104 are collected in the header 80 and are opened to the atmosphere through the merged vent pipe 90. Thus, it is not necessary to extend the snorkel 74 and the

separate snorkels

103 and 104, respectively, to the outside of the room. This enables air intake and exhaust to be performed collectively, and the number of components can be reduced as compared with the case where the breather pipe 74 and the

independent breather pipes

103 and 104 are arranged so as to be open to the atmosphere.

[ reference example 1]

In fig. 14, in the drain structure 56 of the present reference example, the 1 st siphon drain pipe 31 is connected to the downstream side of the drain pipe 51 extending from the 1 st drain trap 21. Further, a 2 nd siphon drain pipe 32 is connected to a downstream side of the drain pipe 52 extending from the 2 nd drain trap 22. That is, the drainage path from the 1 st drainage trap 21 and the drainage path from the 2 nd drainage trap 22 are independent of each other.

Therefore, even if the water is collected and drained from the 1 st drain trap 21, the drain does not flow into the 2 nd drain trap 22. Therefore, the accumulated drain from the bathtub 11 can be prevented from overflowing into the shower 12.

[ reference example 2]

In fig. 15, the drainage structure 66 of the present reference example is provided with

suction valves

111 and 112 in addition to reference example 1. A branch pipe 121 extending upward is connected to the drain pipe 51. The suction valve 111 is provided at the upper end of the branch pipe 121. A branch pipe 122 extending upward is connected to the drain pipe 52. Further, the suction valve 112 is provided at the upper end of the branch pipe 122. The configuration of the

intake valves

111 and 112 is the same as that of the intake valve 30 of embodiment 1.

In this reference example, as in reference example 1, even if the water is collected and drained from the 1 st drain trap 21, the drain does not flow into the 2 nd drain trap 22. Therefore, the accumulated drain from the bathtub 11 can be prevented from overflowing into the shower 12.

Since the suction valve 111 is added to the drain pipe 51, external air is introduced from the suction valve 111 when water is discharged from the 1 st drain trap 21. Since the suction valve 112 is added to the drain pipe 52, external air is introduced from the suction valve 112 when water is discharged from the second drain trap 22. Therefore, the drain from the 1 st drain trap 21 and the drain from the 2 nd drain trap 22 both flow easily.

Since the other portions are the same as those in embodiment 1 or reference example 1, the same reference numerals are given to the same portions in the drawings, and the description thereof is omitted.

[ 6 th embodiment ]

In fig. 16, the drain structure 86 of the present embodiment includes the 2 nd bypass pipe 218. The 2 nd bypass pipe 218 connects the 1 st drain trap 21 side in the 1 st bypass pipe 18 and the 2 nd drain trap 22 side in the 1 st bypass pipe 18 at a position lower than the uppermost portion of the 1 st bypass pipe 18. The bottom surface of the pipe in the 2 nd bypass pipe 218 is disposed lower than the top surface 22A of the 2 nd drain trap 22. The bottom surface of the pipe passage in the 2 nd bypass pipe 218 is disposed higher than the bottom surface 52D of the upper cross pipe portion 52A of the drain pipe 52.

The 2 nd bypass duct 218 extends, for example, in the lateral direction. The 2 nd bypass pipe 218 may be inclined or bent with respect to the horizontal direction. In the case where the height of the bottom surface of the pipe passage in the 2 nd bypass pipe 218 is not constant in this way, the highest position in the bottom surface is disposed lower than the top surface 22A of the 2 nd drain trap 22 and higher than the bottom surface 52D of the upper cross pipe portion 52A.

A 1 st check valve 19 is provided at, for example, a connection portion 18D in the 1 st bypass pipe 18. The 1 st check valve 19 is configured to allow a flow from the 2 nd drain trap 22 side to the 1 st drain trap 21 side, but not to allow a flow from the 1 st drain trap 21 side to the 2 nd drain trap 22 side. The position of the 1 st check valve 19 is not limited to the connecting portion 18D, and may be provided in the vertical pipe portion 18B, for example. The 1 st check valve 19 may be configured to allow a flow from the 1 st drain trap 21 side to the 2 nd drain trap 22 side to some extent.

The 2 nd bypass pipe 218 is provided with a 2 nd check valve 219. The 2 nd check valve 219 is configured to allow a flow from the 2 nd drain trap 22 side to the 1 st drain trap 21 side, but not to allow a flow from the 1 st drain trap 21 side to the 2 nd drain trap 22 side. The 2 nd check valve 219 may be configured to allow a flow from the 1 st drain trap 21 side to the 2 nd drain trap 22 side to some extent.

Even when the drain from the shower 12 does not completely enter the 2 nd drain trap 22 and becomes full, according to the present embodiment, the excess drain flows through the 2 nd bypass pipe 218 from the vertical pipe portion 51B and the lower horizontal pipe 51C of the drain pipe 51 toward the 1 st siphon drain pipe 31 (fig. 1) (in the direction of arrow H). In the present embodiment, the bottom surface of the pipe passage in the 2 nd bypass pipe 218 is disposed higher than the bottom surface 52D of the upper cross pipe portion 52A of the drain pipe 52. Therefore, the drain from the shower 12 does not flow to the 2 nd bypass pipe 218 frequently, and the 2 nd siphon drain pipe 32 can be quickly brought to full flow, and therefore, a siphon start delay is not caused.

In the present embodiment, the bottom surface of the pipe passage in the 2 nd bypass pipe 218 is disposed lower than the top surface 22A of the 2 nd drain trap 22. Therefore, when the drain overflows from the 2 nd drain trap 22, the drain flows to the 2 nd bypass pipe 218, and therefore the drain can be suppressed from overflowing from the 2 nd drain trap 22.

Further, since the 2 nd check valve 219 is provided in the 2 nd bypass pipe 218, the flow from the 1 st drain trap 21 side to the 2 nd drain trap 22 side through the 2 nd bypass pipe 218 is suppressed. Further, since the 1 st check valve 19 is provided in the connecting portion 18D of the 1 st bypass pipe 18, when water is discharged from the bathtub 11, the flow from the 1 st drain trap 21 side to the 2 nd drain trap 22 side via the 1 st bypass pipe 18, that is, the overflow from the vertical pipe portion 18A to the vertical pipe portion 18B is more unlikely to occur.

[ 7 th embodiment ]

In fig. 17, the drain structure 76 of the present embodiment is configured such that the 1 st check valve 19 of the 1 st bypass pipe 18 in embodiment 6 is omitted. In the 1 st bypass pipe 18, as described in embodiment 1, by appropriately setting the height of the uppermost portion 18H, overflow between the

vertical pipe portions

18A, 18B in the 1 st bypass pipe 18 can be prevented. Therefore, by omitting the 1 st check valve 19 as in the present embodiment, the structure can be simplified and the cost can be reduced.

[ 8 th embodiment ]

In fig. 18, the drain structure 130 of the present embodiment includes a 1 st drain trap 132. The 1 st drain elbow 132 has an elbow main body 132A provided on the downstream side of the drain portion 41 and formed in a tubular shape. The elbow main body 132A has a 1 st channel 132C, a 2 nd channel 132D, a 3 rd channel 132E, and a 4 th channel 132F. The 1 st flow path portion 132C extends downward at a position corresponding to the drain portion 41, that is, below the drain portion 41, and is bent in a horizontal direction at a middle portion thereof. Specifically, the 1 st flow path portion 132C includes a portion 132CC extending downward and a portion 132CB extending horizontally from a lower end of the portion 132CC extending downward, and the portion 132CB extending horizontally is placed on the floor 24 (see fig. 1). That is, the 1 st flow path portion 132C is set to a range from the end portion 132CA on the bathtub 11 side in the 1 st drain trap 132 to the boundary B1 between the portion 132CB extending in the horizontal direction and the 2 nd flow path portion 132D.

The 2 nd flow path portion 132D is provided adjacent to the 1 st flow path portion 132C on the downstream side of the 1 st flow path portion 132C, and extends obliquely upward with respect to the downstream end portion (portion 132CB extending in the horizontal direction) of the 1 st flow path portion 132C. That is, the 2 nd flow path unit 132D is provided in a range from the boundary B1 to the boundary B2 between the portion extending diagonally upward and the portion extending horizontally of the 3 rd flow path unit 132E.

The 3 rd flow path portion 132E is provided adjacent to the 2 nd flow path portion 132D on the downstream side of the 2 nd flow path portion 132D, and includes a portion 132EB and a portion 132EA extending in the horizontal direction, and the portion 132EB extends obliquely downward with respect to the portion 132EA extending in the horizontal direction in the 3 rd flow path portion 132E extending from the downstream end portion of the 2 nd flow path portion 132D. The portion 132EA of the 3 rd flow path portion 132E extending in the horizontal direction extends in the horizontal direction from the boundary B2 with the 2 nd flow path portion 132D, and is spaced apart from the floor slab 24 (see fig. 1). The portion 132EB of the 3 rd flow path portion 132E extending obliquely downward extends obliquely downward, that is, toward the floor slab 24 side, from the portion 132EA extending in the horizontal direction. That is, the 3 rd flow path section 132E is provided in a range from the boundary B2 to the boundary B3 between the portion 132EB extending obliquely downward and the 4 th flow path section 132F.

The 4 th flow path portion 132F is provided adjacent to the 3 rd flow path portion 132E on the downstream side of the 3 rd flow path portion 132E, extends in the horizontal direction, and is placed on the floor 24 (see fig. 1). That is, the 4 th flow path portion 132F is provided in a range from the boundary B3 to the end to which the 1 st siphon drain pipe 31 is connected. The lower end of the 2 nd flow path part 132D is at the same height as the 4 th flow path part 132F, and is placed on the floor slab 24. In other words, the 1 st drain trap 132 has a structure in which the drain pipe 51 is integrally provided. The lower end of the 2 nd flow path part 132D is at the same height as the 4 th flow path part 132F, but the present invention is not limited thereto, and when the lower end of the 2 nd flow path part 132D is at a different height from the 4 th flow path part 132F, at least the 4 th flow path part 132F may be placed on the floor slab 24.

According to the above configuration, the 1 st drain trap 132 partially has the convex portion 134 facing upward. A water seal reservoir 136 is formed in the projection 134 on the 1 st flow path portion 132C side.

The upper side (upstream side) of the opening of the 1 st flow path portion 132C in the 1 st drain trap 132 on the bathtub 11 side is expanded in diameter relative to the lower side (downstream side). In other words, the opening of the 1 st drain trap 132 on the bathtub 11 side projects radially outward with respect to the portion other than the opening.

A 1 st elbow wall 132ED as a relief portion is formed in the bottom wall 132BB of the 3 rd flow path portion 132E at a portion 132EA extending in the horizontal direction, which is located at a vertex of the 2 nd flow path portion 132D extending upward of the bottom wall 132BB of the convex portion 134 of the 1 st drain elbow 132. The 1 st elbow wall 132ED projects upward in a portion 132EA extending in the horizontal direction, with the direction from the upstream side to the downstream side being the plate thickness direction.

On the other hand, a 2 nd elbow wall 132CD as a convex portion is formed on the upper wall 132B of the 1 st elbow wall 132 on the upstream side of the 1 st elbow wall 132 ED. The 2 nd bent pipe wall 132CD has a plate thickness direction in a direction from the upstream side to the downstream side, and protrudes downward from the upper portion. The projecting amount of each of the 1 st elbow wall 132ED and the 2 nd elbow wall 132CD is set to a degree that can ensure a required water seal.

The 1 st bypass pipe 18 is connected to a portion of the convex portion 134 of the 1 st drain trap 132 above the water seal reservoir 136. Specifically, the 1 st bypass pipe 18 is connected substantially horizontally above a portion 132EB of the convex portion 134 of the 1 st drain elbow 132, the portion 132EB extending obliquely downward from the 3 rd flow path portion 132E. The 1 st bypass pipe 18 is more preferably inclined gradually so as to become higher as it is farther from the 1 st drain trap 132 in view of performing drainage. The 1 st bypass pipe 18 is disposed in the gap S (see fig. 1) from between the shower 12 and the floor 24 (see fig. 1).

Since the diameter of the 1 st drain trap 132 is set larger than the diameter of the normal drain pipe 51, which is not shown, the area of the flow path at the portion where the 2 nd trap wall 132CD is formed and the area of the flow path at the portion where the 1 st trap wall 132ED is formed can be set larger than the area of the flow path in the normal thick pipe. This can suppress clogging.

In the present embodiment, since the basic configuration is the same as that of embodiment 1, the same operational effects as those of embodiment 1 can be obtained.

[ 9 th embodiment ]

In fig. 19, the drain structure 140 of the present embodiment is configured such that the 1 st bypass pipe 18 connected to the convex portion 134 of the 1 st drain trap 132 in embodiment 8 is vertically connected to the 4 th flow path portion 132F penetrating the wall portion 12A. In the present embodiment, since the basic configuration is the same as that of embodiment 1, the same operational effects as embodiment 1 can be obtained, and further, by providing the 1 st bypass pipe 18 in the wall portion 12A, the floor can be further lowered.

[ other embodiments ]

While the embodiments of the present invention have been described above as examples, it goes without saying that the embodiments of the present invention are not limited to the above-described embodiments, and can be implemented by being variously modified in addition to the above-described embodiments without departing from the scope of the invention.

The bathtub 11 is exemplified as an example of the water using device, but the water using device may be a device that discharges water into a collected water such as a washing machine. The shower 12 is exemplified as another water-using appliance, but the other water-using appliance may be an appliance that discharges water continuously, such as a sink, a kitchen, or a dish washer.

The suction valve 30 is provided in the 1 st bypass pipe 18, but the suction valve 30 may be omitted if the water seal of the 1 st drain trap 21 and the 2 nd drain trap 22 is not broken.

Claims

1. A drain trap, wherein,

this drainage return bend has:

a substantially tubular elbow main body portion provided downstream of a drain portion provided at a bottom of the water using appliance and having a portion extending downward and a portion extending horizontally from a lower end of the portion extending downward; and

and a convex portion provided on an upper wall in the elbow main body, the convex portion protruding downward such that a tip end portion thereof is closer to a bottom wall of the elbow main body than other portions.

2. The drain trap according to claim 1,

the drain trap includes an overflow portion provided at a portion of the bottom wall in the trap body portion on the downstream side of the convex portion, and the overflow portion protrudes upward so that a tip end portion thereof is closer to the upper wall of the trap body portion than other portions and is located higher than the tip end portion of the convex portion.

3. The drain trap according to claim 2,

an inclined portion extending obliquely upward with respect to a bottom wall of a portion of the bent pipe main body portion extending in the horizontal direction is provided between the convex portion and the overflow portion in the bent pipe main body portion.

4. The drain trap according to claim 2 or 3,

in the elbow main body portion, a width of a flow path between a tip end portion of the overflow portion and an upper wall of the elbow main body portion is formed larger than a width of the drain portion.

5. The drain trap according to any one of claims 2 to 4,

a breather pipe is connected substantially horizontally to a downstream side of the elbow main body portion with respect to the overflow portion.

6. The drain trap according to any one of claims 1 to 5,

in the elbow main body, a width of a flow path between a tip end of the convex portion and a bottom wall of the elbow main body is formed larger than a width of the drain portion.

7. The drain trap according to any one of claims 1 to 6,

the projection is formed such that the amount of projection toward the lower side gradually increases from the upstream side toward the downstream side in the elbow main body.