Branch pipe joint

Abstract

To provide a branch pipe joint that is used at a connection part between a main pipe and an attaching pipe, and can prevent breakage of a component with flexibility even if an inner pressure of the main body becomes high.SOLUTION: A branch pipe joint connecting a main pipe P and an attaching pipe B is equipped with a body 11, a socket 37, a flexible pipe 35, and a protector 41. The body 11 is fixed to a side peripheral surface of the main pipe P. The socket 37 has a cylindrical shape into which the attaching pipe B is inserted, and the flexible pipe 35 is a channel having flexibility capable of absorbing displacement of the main pipe P and the attaching pipe B, and is adjacent to the socket 37. The protector 41 has an annular shape surrounding the side peripheral surface of the flexible cylinder 35, and restrains expansion of the flexible cylinder 35. Therefore, even if an inner pressure of the main pipe P becomes high, the flexible cylinder 35 can be prevented from strongly contacting with a peripheral subsoil, and the breakage thereof can be avoided. By making the protector 41 in a dividable structure, workability at constructing is improved, and manufacturing cost can be suppressed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a branch pipe joint used at the connection point between a main pipe with a large cross section and an attachment pipe with a small cross section in an irrigation canal, sewer, or the like. [Background technology]

[0002] Irrigation channels and sewers are essential social infrastructure for people's lives, and for sanitary reasons, open channels are never used for sewers; instead, large main pipes are buried underground, to which lateral pipes extending from homes and other facilities are connected. In contrast, irrigation channels are often open channels, but for safety reasons, underground channels or pipes are sometimes used, in which case the lateral pipes are connected to the main pipe, just like sewers. In this way, when irrigation channels, sewers, etc. are composed of a main pipe and lateral pipes, the two are sometimes connected via some kind of branch pipe joint to prevent water leakage at the connection point.

[0003] Various technological developments have been made on branch pipe joints from the viewpoints of reliability and workability, and an example of such developments is Patent Document 1, which is mentioned below. This document discloses a "connection joint for an attachment pipe" that can simplify the work of connecting an attachment pipe, and this connection joint is composed of a joint body, a fitting body, a locking means, etc., and the joint body is cylindrical and arranged to connect the main pipe (main pipe) and the attachment pipe, and has a male thread formed on its outer circumferential surface.

[0004] The fitting is cylindrical and surrounds the joint body. One end of the fitting is placed on the outer periphery of the main pipe via a pressing member and a packing. Its inner periphery has a female thread that threads onto the male thread. The locking means is L-shaped, consisting of an upper arm and a lower locking claw. It is shaped so that it can be locked onto the inner periphery of the joint body. The locking claw can enter the main pipe through the main pipe's connection port. During installation, the locking claw is inserted into the main pipe, the fitting is placed on the outer periphery of the main pipe, and the fitting is then rotated. The male thread and female thread engage, pulling up the locking claw. The main pipe is sandwiched between the locking means and the packing, securing the joint to the main pipe.

[0005] The joint body in Patent Document 1 incorporates a tubular rubber gasket on the opposite side of the main pipe. After the attachment pipe is inserted into the inner surface, the rubber gasket adheres tightly to the attachment pipe by tightening the attachment band. The rubber gasket is easily deformed, offering various advantages, such as absorbing misalignment between the main pipe and the attachment pipe and preventing the attachment pipe from falling off in the event of an earthquake. For this reason, branch pipe joints with this type of configuration have become more common in recent years. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 8-14467 Summary of the Invention [Problem to be solved by the invention]

[0007] Irrigation channels and sewers often have a sloped main pipe to allow water to flow naturally, so the internal pressure of the main pipe does not build up. However, depending on the terrain, pumping stations may be installed along the way, which can cause internal pressure to build up. Internal pressure can also temporarily rise if the flow rate changes significantly in a short period of time due to the opening or closing of gates. If the internal pressure of the main pipe suddenly rises for some reason, the components that make up the branch pipe fittings can become significantly deformed, which can lead to water leaks or the detachment of the connecting pipe.

[0008] As with the branch pipe joints described in Patent Document 1, flexible parts made of rubber or other materials are sometimes incorporated. If the internal pressure of the main pipe increases for some reason, these parts expand and come into violent contact with the surrounding ground. If the ground contains stones with sharp corners, repeated contact can cause further damage to the parts, ultimately leading to problems such as water leaks. Therefore, to prevent this damage, some kind of measure must be taken during the construction stage, and it is desirable that these measures be low-cost and easy to install.

[0009] The present invention was developed based on these circumstances, and aims to provide a branch pipe fitting that can be used at the connection between a main pipe and an attachment pipe and can prevent damage to flexible parts even if the internal pressure of the main pipe becomes high. [Means for solving the problem]

[0010] The invention described in claim 1 for solving the above problem is a branch pipe joint used to connect a main pipe and an attachment pipe branching off from the main pipe, comprising a main body, a socket, a flexible tube, a bottom opening, and a protector, the main body is fixed to the side surface of the main pipe, the socket is tubular into which the attachment pipe is inserted, the flexible tube is a flexible flow path that can absorb displacement between the main pipe and the attachment pipe, and is adjacent to the socket and is provided between the socket and the bottom opening, the main body is Inner tube into which the bottom opening is fitted and the body has Inner cylinderThe protective device is connected to the bottom opening with its upper end separated from the lower end of the attachment tube inserted into the receiving opening, the protective device is annular and surrounds the side surface of the flexible tube, restraining the expansion of the flexible tube, and the protective device is arranged on the side surface of the flexible tube inside which the attachment tube and the main body are not arranged.

[0011] The branch pipe joint of the present invention is designed to withstand high internal pressure and is composed of a main body, a socket, a flexible tube, and a protective device, of which the main body is a base portion fixed to the side surface of the main pipe. The socket is a tubular portion into which the lateral pipe can be fitted. The flexible tube is a tubular portion that protrudes from the main body and is connected to the socket. It functions as a flow path between the main pipe and the lateral pipe, and literally absorbs displacement between the main pipe and the lateral pipe.

[0012] There are various methods for fastening the main body to the main pipe, and specific examples include using a claw-like object to contact the inner surface of the main pipe and tightly fasten the main body to the main pipe, wrapping a belt around the main pipe and fastening the main body with this belt, or fastening the main body via a ring or the like that is tightly fastened to the inner surface of the mounting hole of the main pipe. By fastening the main body to the main pipe in this way, water can pass through the inside of the main body without leaking.

[0013] The flexible tube is a cylindrical tube made of a flexible material such as rubber or soft resin, and is placed between the main body and the socket. One end of the flexible tube is connected to the main body in a leak-proof manner, and the other end is connected to the socket. The flexible tube's elastic deformation allows for free adjustment of the intersection angle between the main pipe and the lateral pipe during installation, and can easily accommodate any displacement between the main pipe and lateral pipe caused by deformation over time or earthquakes after installation. The flexible tube and the lateral pipe are often molded as a single unit.

[0014] The protective gear is a cylindrical piece that covers the side periphery of the flexible tube, and its role is to push back the flexible tube when it expands due to increased internal pressure. For this reason, the protective gear is made of a material such as metal, and must be strong enough to withstand the load transmitted from the flexible tube. It must also be an unbroken ring to seamlessly prevent deformation of the flexible tube. However, due to its intended use, the flexible tube must be able to tolerate a certain degree of deformation, and the protective gear's shape takes this into account.

[0015] In this way, by configuring the branch pipe joint with the main body, socket, flexible pipe, and protective device, and by incorporating the protective device so that it surrounds the side surface of the flexible pipe, the expansion of the flexible pipe is restrained by the protective device even if the internal pressure of the main pipe increases. This prevents the flexible pipe from coming into violent contact with the surrounding ground and avoids damage to the flexible pipe.

[0016] The invention described in claim 2 relates to the configuration of the protective equipment, which can be divided into multiple parts. A gap is formed between the protective device disposed on the flexible tube and the flexible tube. This is characterized by the fact that the protective equipment has a divided structure, so that the protective equipment is placed so as to surround the flexible tube, and then the two are integrated to complete the assembly. By making the protective equipment a divided structure in this way, there is no need to assemble the protective equipment before connecting the mounting pipe, which is easy to work with. In addition, the protective equipment can be completed simply by deforming the metal plate, which helps to reduce manufacturing costs. The method of integrating the divided protective equipment can be freely selected, such as bolting. [Effects of the Invention]

[0017] In a branch pipe joint equipped with a flexible tube that can absorb displacement between the main pipe and the attachment pipe, as in the invention described in claim 1, by incorporating a protector that surrounds the side surface of the flexible tube, the expansion of the flexible tube is restrained by the protector. Therefore, even if the internal pressure of the main pipe increases, the flexible tube is prevented from coming into violent contact with the surrounding ground, and damage to the flexible tube can be avoided.

[0018] As in the invention of claim 2, by making the protector separable, the protector can be assembled after connecting the mounting pipe to the branch pipe joint during installation, which is easy to work with. In addition, its manufacture can be completed by simply pressing and drilling the metal plate, so there is no increase in costs. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a perspective view showing an example of the configuration of a branch pipe joint according to the present invention. [Figure 2] FIG. 2 is a perspective view showing the internal structure of the branch pipe joint of FIG. [Figure 3] FIG. 10 is a perspective view showing the state in which the main body is fixed to the main pipe. [Figure 4] This is a perspective view showing the stage where the main pipe and the attachment pipe have been connected and the protective device is being installed. [Figure 5] FIG. 5 is a perspective view showing a stage after FIG. 4 in which the installation of the protector has been completed. DETAILED DESCRIPTION OF THE INVENTION

[0020] Figure 1 shows an example of the configuration of a branch pipe fitting according to the present invention. The branch pipe fitting is used to connect a main pipe P and an attachment pipe B, and this figure shows the branch pipe fitting before it is brought into contact with the main pipe P. The main pipe P at the bottom of the figure is a large-diameter pipe intended for use as a trunk line and is buried underground, while the attachment pipe B is a small-diameter pipe that functions as a branch line connecting the main pipe P to homes, etc. A circular mounting hole H is drilled into the main pipe P for connection to the attachment pipe B. Note that only the upper half of the main pipe P is shown in the figure due to space constraints, but it actually has a circular cross section.

[0021] The branch pipe fitting in this figure is broadly composed of a main body 11, a locking device 21, a connecting device 31, and a protective device 41. Of these, the main body 11 is a base portion fixed to the side surface of the main pipe P, and has multiple parts such as a skirt 13, an outer tube 14, and a sleeve 17, through which water flows. The skirt 13 is arc-shaped to fit the side surface of the main pipe P, and makes contact with the main pipe P without any gaps, stabilizing the position of the branch pipe fitting. The outer tube 14 is arranged to surround the mounting hole H, and functions as the base portion of the attachment pipe B.

[0022] Connector 31 connects main body 11 and attachment pipe B, is integrally molded from a material such as rubber, and has multiple parts, such as socket 37, flexible tube 35, and ridges 34 and 36, which easily undergo elastic deformation when subjected to external force. Socket 37 is located at the upper end of the branch pipe joint and is the part responsible for connecting to attachment pipe B, with its inner diameter matching the outer diameter of attachment pipe B. After attachment pipe B is inserted into the inner surface of socket 37, a fastening band 39 is assembled to surround socket 37 and tightened, making it impossible for attachment pipe B to come off socket 37.

[0023] The flexible tube 35 is a bellows-shaped section adjacent to the socket 37, and serves to absorb displacement between the main pipe P and the attachment pipe B. Therefore, the wall thickness of the flexible tube 35 is restricted, and it will expand outward when the internal pressure increases. To perform this function, the flexible tube 35 is given a certain degree of extension. Furthermore, annular ridges 34 and 36 are provided on the top and bottom of the flexible tube 35. The ridges 34 and 36 serve to separate the flexible tube 35 from other areas, and are larger in diameter than the flexible tube 35. In addition, the lower end of the connector 31 is fitted into the main body 11, and a fastening band 39 is also incorporated here to prevent it from separating from the main body 11.

[0024] The locking device 21 serves to secure the main body 11 to the main pipe P, and its lower end passes through the mounting hole H and enters the inside of the main pipe P. Additionally, in the main body 11, the sleeve 17 located above the outer tube 14 is rotatable relative to the outer tube 14, and the locking device 21 can be pulled up by turning the handle 18 protruding from the sleeve 17. Therefore, when the locking device 21 is actually pulled up, the main pipe P is sandwiched between the locking device 21 and the skirt 13, and the main body 11 is fixed to the main pipe P.

[0025] The protective device 41 is a metal part that surrounds the side surface of the flexible tube 35 and serves to restrain the expansion of the flexible tube 35. The protective device 41 in this figure is not ring-shaped but is split in half, and each protective device 41 is composed of a restraining band 45 and a flange 43. The restraining band 45 is semicircular and slightly larger than the diameter of the flexible tube 35, and its width (vertical direction in the figure) matches the extension of the flexible tube 35. In addition, flat flanges 43 are provided on both ends of the restraining band 45, and a circular hole 44 is formed near the center. The flanges 43 of the opposing protective devices 41 are then brought into contact with each other, and the circular holes 44 of both are aligned concentrically. A bolt 48 is inserted into the holes, and a nut 49 is screwed onto the tip of the bolt 48 protruding from the circular hole 44. Finally, the bolt 48 and the nut 49 are tightened, so that the flanges 43 come into close contact with each other, and the flexible tube 35 is seamlessly surrounded by the protective device 41. The protective equipment 41 in this figure has a simple shape and can be completed by simply bending and drilling a metal plate.

[0026] Figure 2 shows the internal structure of the branch pipe joint in Figure 1. The main body 11 is composed of a skirt 13, an outer tube 14, an inner tube 15, and a sleeve 17. The skirt 13 is arc-shaped and fits tightly against the side surface of the main pipe P, and is positioned to close the mounting hole H. The outer tube 14 is molded integrally with the skirt 13, and is positioned to surround the mounting hole H. Furthermore, the inner tube 15 is incorporated inside the outer tube 14, and water passes through the inner tube 15. The inner tube 15 is vertically displaceable relative to the outer tube 14.

[0027] The sleeve 17 is an annular member that rests on the outer tube 14 and is rotatable relative to the outer tube 14. A plate-shaped handle 18 protrudes from the side circumferential surface of the sleeve 17 in consideration of the actual rotation of the sleeve 17. The inner tube 15 is fitted into the inner circumferential surface of the sleeve 17, and a threaded portion 16 is formed at the boundary between the two. This threaded portion 16 is composed of a male thread on the inner tube 15 side and a female thread on the sleeve 17 side, and rotating the sleeve 17 displaces the inner tube 15 in the vertical direction. The sleeve 17 is rotatable relative to the outer tube 14, but is designed so that it cannot be detached from the outer tube 14.

[0028] The connector 31 is made of rubber, and is formed by integrally molding the bottom opening 33, flexible tube 35, socket 37, and ridges 34 and 36. The bottom opening 33, which is located at the bottom, is fitted into the inner tube 15. To prevent the connector 31 from coming loose at this point, a fastening band 39 is incorporated, as shown in Figure 1 above. The flexible tube 35 is shaped like a bellows, and can be freely deformed to a certain extent. In addition, the socket 37 has a step on its inner surface to ensure proper insertion of the attachment tube B, and the end face of the attachment tube B comes into contact with this step.

[0029] Two locking devices 21 are arranged on either side of the center of the mounting hole H, and each locking device 21 is composed of a head 25, an arm 24, and a claw 23, and is attached to the inner surface of the inner tube 15 in a manner that allows it to swing. The head 25 of the locking device 21 is a slightly thicker part, and by fitting into the inner surface of the inner tube 15, the inner tube 15 and the locking device 21 are firmly integrated. The claw 23 enters the inside of the main pipe P through the mounting hole H, and by further displacing the claw 23 outward from the mounting hole H, it becomes possible to pull the main body 11 toward the main pipe P. In addition, the arm 24 connects the head 25 and the claw 23, and serves to allow the claw 23 to reach the inside of the main pipe P. The head 25 is attached in a swingable state relative to the inner tube 15, and when inserting the claws 23 into the main pipe P, the locking device 21 is tilted inward as shown in this figure, but once the insertion is complete, the locking device 21 is returned to its original state and the claws 23 are displaced outside the mounting hole H.

[0030] FIG. 3 shows the state in which the main body 11 is fixed to the main pipe P. As shown in FIG. 2, the skirt 13 is brought into contact with the main pipe P while the locking device 21 is tilted inward. Then, when the locking device 21 is raised upright, the claws 23 are displaced outward from the mounting hole H, as shown in this figure. At this stage, the skirt 13 is merely in contact with the main pipe P. However, when the sleeve 17 is subsequently rotated via the handle 18, the inner tube 15 is displaced upward, and the claws 23 are pulled up together with it. As a result, the main pipe P is sandwiched between the claws 23 and the skirt 13, and the branch pipe fitting is fixed to the main pipe P. Next, the attachment pipe B is inserted into the socket 37 and secured with the fastening band 39, completing the connection between the main pipe P and the attachment pipe B. Note that the head 25 of the locking device 21 is fitted into the inner circumferential surface of the inner tube 15, so the locking device 21 displaces integrally with the inner tube 15.

[0031] Figure 4 shows the stage where the main pipe P and the annex pipe B are connected and the protector 41 is installed. After the branch pipe coupling is fixed to the main pipe P and the main pipe P and annex pipe B are connected as shown in Figure 3, two protectors 41 are placed facing each other to sandwich the flexible tube 35, as shown in this figure. When these protectors are brought close together so that their flanges 43 come into contact, the flexible tube 35 is surrounded by the protector 41. At this time, the protector 41 is sandwiched between the upper and lower ridges 34 and 36 and cannot be removed from the flexible tube 35. Therefore, the protector 41 does not need to be tightly attached to the flexible tube 35; a certain amount of clearance can be maintained, allowing the flexible tube 35 to deform. As a result, even after the protector 41 is installed, the intersection angle between the main pipe P and annex pipe B can be freely adjusted and displacement between the main pipe P and annex pipe B can be accommodated.

[0032] Figure 5 shows the stage after Figure 4, when the protective device 41 has been installed. After the flanges 43 of the opposing protective devices 41 are brought into contact with each other, a bolt 48 is inserted through them. A nut 49 is then threaded onto the tip of the bolt 48 and tightened, resulting in the flexible tube 35 being continuously surrounded by the protective device 41. Therefore, even if the internal pressure increases for some reason and the flexible tube 35 expands, it is restrained by the protective device 41, preventing the flexible tube 35 from coming into violent contact with the surrounding ground. Note that in this figure, the mounting tube B is upright, but due to the elastic deformation of the flexible tube 35, there is no problem even if the mounting tube B tilts to some extent. To accommodate this, a certain amount of clearance is provided between the flexible tube 35 and the protective device 41.

[0033] The present invention is characterized in that the flexible tube 35 of the branch pipe joint is surrounded by a protective device 41, and the specific configuration of the branch pipe joint can be freely selected. Therefore, the branch pipe joint shown in the series of figures is merely an example. However, it is assumed that the branch pipe joint always has a flexible tube 35 made of rubber or other material. [Explanation of symbols]

[0034] 11 Main unit 13 Skirt 14 outer cylinder 15 Inner cylinder 16 Threaded part 17 Sleeve 18 Handle 21 Locking device 23 Claws 24 Arm 25 heads 31 Connectors 33 Bottom mouth 34 Convex stripe (bottom in the figure) 35 Flexible tube 36 Convex strip (upper side in the figure) 37 Underbite 39 Fastening band 41 Protective Equipment 43 Spit 44 round hole 45 Restraint Belt 48 volts 49 Nut B Mounting pipe H Mounting hole P main

Claims

1. A branch pipe joint used to connect a main pipe (P) and an attachment pipe (B) branching off from the main pipe (P), comprising a main body (11), a socket (37), a flexible tube (35), a bottom opening (33), and a protective element (41); The main body (11) is fixed to the side peripheral surface of the main pipe (P), the socket (37) is cylindrical and the attachment pipe (B) is inserted into it, and the flexible tube (35) is a flexible flow path that can absorb displacement between the main pipe (P) and the attachment pipe (B), and is adjacent to the socket (37) and is provided between the socket (37) and the bottom opening (33). The main body (11) has an inner cylinder (15) into which the bottom opening (33) is fitted, The main body (11) is connected to the bottom opening (33) in a state where the upper end of the inner tube (15) is separated from the lower end of the attachment pipe (B) inserted into the socket (37), The protective member (41) is annular and surrounds the side circumferential surface of the flexible tube (35), and restrains the expansion of the flexible tube (35). A branch pipe joint characterized in that the protective device (41) is arranged on the side surface of the flexible tube (35) on the inside of which the attachment pipe (B) and the main body (11) are not arranged.

2. The protective equipment (41) can be divided into multiple parts, 2. The branch pipe joint according to claim 1, wherein a gap is formed between the protective member (41) disposed on the flexible tube (35) and the flexible tube (35).

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