JP5103149B2 - Branch pipe connection device, connection adapter and branch pipe connection method - Google Patents

Description

  The present invention relates to a branch pipe connection device that enables a branch pipe to be connected to an existing pipe, a connection adapter that constitutes the branch pipe connection device, and a branch pipe connection method using the branch pipe connection device.

  In recent years, in branch pipe connection work where branch pipes are installed in the middle of existing fluid pipes such as water pipes, the peripheral walls of existing pipes are perforated while maintaining the state of uninterrupted water without stopping water on the upstream side. However, a method of connecting branch pipes is adopted. In such a construction method, as disclosed in Patent Document 1 below, a branch case made of a split body that can be watertightly attached to an existing pipe, an end on one side is connected to the branch case, and an end on the other side is connected to the branch pipe. A branch pipe connecting device provided with a gate valve connectable to is used.

  18 and 19 are front views for explaining an example of a conventional branch pipe connecting device. This device includes a bifurcated case 51 that is divided into left and right parts, and a gate valve 52 that is flange-connected to the branch case 51. At the time of construction, first, as shown in FIG. 18, the branch case 51 is externally fitted to the existing pipe K, the divided surfaces are flange-connected, and mounted in a watertight state. Then, the flange portion 51a of the branch case 51 and the flange portion 52a of the gate valve 52 are fastened with bolts and nuts, and the branch case 51 and the gate valve 52 are connected with the top portion 52c of the gate valve 52 facing upward. .

  Next, the flange 52 b of the gate valve 52 and the flange 53 a of the punching device 53 are fastened with bolts and nuts, and the punching device 53 is connected to the gate valve 52. Although not shown, inside the drilling device 53, there is a rotating shaft configured to be rotatable by a drive unit, a cylindrical hole saw provided at the tip of the rotating shaft, and a drill protruding forward from the center position of the hole saw. And built-in. The hole saw is configured to move forward and backward together with a drill by a feed handle 54 provided at the rear of the punching device 53.

  After connecting the perforating device 53 to the gate valve 52, the valve body of the gate valve 52 is retracted upward to open the gate valve 52 in a communicating state. Subsequently, while rotating the hole saw, the feed handle 54 is rotated and fed to the existing pipe K side, and the peripheral wall of the existing pipe K is perforated. When the drilling is completed, the rotation of the hole saw is stopped, and the feed handle 54 is reversely rotated to retract the hole saw. A part of the peripheral wall of the cut-out existing pipe is collected by being caught by a drill.

  After sufficiently retracting the hole saw, the valve body of the gate valve 52 that has been retracted upward is lowered to close the communication state. Then, as shown in FIG. 19, the punching device 53 is removed, and a branch pipe 55 is connected instead. In this example, the flange portion 52b of the gate valve 52 and the flange portion 56a of the connection pipe 56 are fastened with bolts and nuts, and the tip of the branch pipe 55 is inserted into a receiving port provided in the connection pipe 56, whereby the gate valve 52 and the branch pipe 55 are connected. According to such a branch pipe connection method, since the branch pipe is provided without water shutoff, convenience for the user is high.

  However, in the prior art as described above, since the connection points such as the split surface of the branch case connected to the flange and the flange portion of each member are located in a direction perpendicular to the axial center direction of the branch pipe, When a large load is applied to a branch pipe or an existing pipe due to aging, etc., there is a problem that the connection portion is easily opened due to the extension of the bolt and the fluid inside the pipe leaks. Normally, piping is buried in the soil, and even if fluid leaks out, it is difficult to detect and countermeasures tend to be delayed, so there are many losses associated with fluid outflow.

  In order to solve this problem, a method may be employed in which the entire connection portion is covered with concrete and hardened. However, it is not always sufficient as a countermeasure such as cracking in concrete or fluid leaking from concrete. In addition, there is a problem that inspection and maintenance work cannot be performed on the connection points.

Further, when connecting a branch pipe to an existing pipe, a branch case of a size that can be externally fitted to the existing pipe and a gate valve of a size that can be connected to each of the branch case and the branch pipe are used. Since there are many cases where the pipe diameter differs from that of the branch pipe and the combinations thereof are various, it is necessary to prepare various branch cases according to various combinations. This is uneconomical because it causes an increase in the cost of manufacturing the mold of the branch case and the number of parts, and there is a technique that can reduce the number of branch cases while solving the problems related to the fluid leakage at the connection points described above. desired.
JP 2002-154004 A

  The present invention has been made in view of the above circumstances, and its purpose is to prevent leakage of fluid from the connection location even if a large load acts on the connection location between the existing pipe and the branch pipe, and An object of the present invention is to provide a branch pipe connection device, a connection adapter, and a branch pipe connection method capable of suppressing the number of cases.

The above object can be achieved by the present invention as described below. That is, the branch pipe connection device according to the present invention includes a branch case that is formed of a split body having a flange portion and can be watertightly attached to an existing pipe, and a gate valve that incorporates a valve body and can be connected to the branch pipe. In the branch pipe connection device that enables the branch pipe to be connected to the existing pipe, the branch pipe is interposed between the branch case and the gate valve, and one end side is extrapolated to the existing pipe side end of the gate valve, The other end side has a cylindrical connection adapter inserted into the branch valve side end of the branch case, and at the split surface of the branch case, the flange portions of the split body are fastened by a fastener, and the and dividing surface is positioned in a substantially horizontal direction, the connection between the branch casing and the connection adapter by engagement of said fastener is Do via the seal material, the partition valve side end of the branch casing, expanded shape 1st inclined surface that inclines and opens outward A protrusion having a second inclined surface that is inclined in a downward direction toward the existing pipe side end of the connection adapter is provided on the outer peripheral surface of the connection adapter, When connecting the connection adapter, the protrusion is fitted into the recess, and the first inclined surface and the second inclined surface are in surface contact with each other .

  In the branch pipe connecting device according to the present invention, the split surface of the branch case connected to the flange is positioned substantially in the horizontal direction, and the connection between the branch case and the connection adapter fastens the flange portions of the split body of the branch case. This is done by tightening the tool. Therefore, even if a heavy load due to ground fluctuation or secular change is applied, the connection location is not located in the opening direction and the load is difficult to act on the fastener, so the fluid inside the piping leaks from the connection location. Can be reliably and effectively prevented. And since this invention interposes a cylindrical connection adapter between a branch case and a gate valve, while the inner diameter of one end side corresponds to the outer diameter of the existing pipe side end part of a gate valve, other By using a connection adapter whose outer diameter on the end side corresponds to the inner diameter of the branch valve side end of the branch case, existing pipes and branch pipes can be connected in various combinations without changing the size of the branch case. be able to. As described above, according to the present invention, it is possible to reduce the number of branch cases while preventing leakage of fluid from the connection portion between the existing pipe and the branch pipe.

As described above , in the branch pipe connecting device according to the present invention, the end portion on the gate valve side of the branch case is formed with a concave portion having a first inclined surface that is inclined to expand in diameter and opens outward, and the connection A protrusion having a second inclined surface is provided on the outer peripheral surface of the adapter, and when the connection adapter is connected to the branch case, the protrusion is fitted into the recess, and the first inclined surface and the second inclined surface DOO has been configured to face contact with each other. According to this configuration, it is possible to easily perform the construction work by preventing the relative rotation between the branch case and the connection adapter while firmly connecting them.

  In the above, as the fastener is tightened, a contact area between the first inclined surface and the second inclined surface is increased, and the first inclined surface presses the second inclined surface, so that from the branch case A concave groove is formed in the inner peripheral surface of the branch case in the vicinity of the gate valve side end portion of the branch case, and the concave groove is formed in the inner peripheral surface of the branch case near the gate valve side end portion. It is preferable that the inner ridge wall to be in contact with an overhang formed on the existing pipe side end surface of the connection adapter so that the connection adapter can be stopped from moving away from the branch case. . According to such a configuration, in addition to the first inclined surface and the second inclined surface being in surface contact, the wedge effect is generated, so that the connection strength between the branch case and the connection adapter can be effectively increased. .

  In the above, one or a plurality of claws projectingly provided on the outer peripheral surface of the existing pipe side end of the gate valve, and the connection adapter is received through the opening and the opening for receiving the claw. It is preferable that the claw is provided with an engagement wall that can be engaged from the direction in which the gate valve is pulled out, and the gate valve and the connection adapter are connected by a bayonet structure. According to this configuration, the gate valve and the connection adapter can be easily and firmly connected.

  In the above, a storage groove for storing the lock ring is formed on the inner peripheral surface of the connection adapter, and the lock ring is formed on a protrusion provided on the outer peripheral surface of the existing pipe side end of the gate valve. What is comprised so that engagement from the extraction direction of the said gate valve is possible is preferable. According to this configuration, the gate valve and the connection adapter can be easily and firmly connected.

Further, the connection adapter according to the present invention is interposed between a branch case made of a divided body having a flange portion and attachable to an existing pipe in a watertight manner, and a gate valve having a built-in valve body and connectable to the branch pipe. One end side is extrapolated to the existing pipe side end of the gate valve, and the other end side is a cylindrical body inserted into the branch valve side end portion of the branch case, and the branch valve side end portion of the branch case fitted possible projections formed recess is provided on the outer peripheral surface, said the projection, the recess surface can contact the first inclined surface that opens outwardly inclined expanded shape has, existing pipe side The 2nd inclined surface which inclines in the direction which goes down toward an edge part is formed.

  According to the connection adapter according to the present invention, the number of branch cases can be reduced while preventing leakage of fluid from the connection point between the existing pipe and the branch pipe as described above. On the other hand, it is possible to configure a branch pipe connection device that can be firmly connected and that can prevent relative rotation with respect to the branch case to facilitate the construction work.

  Further, the branch pipe connection method according to the present invention includes a branch case made of a split body having a flange portion and capable of being watertightly attached to an existing pipe, and a gate valve having a built-in valve body and connectable to the branch pipe. In the branch pipe connection method for connecting the branch pipe to the existing pipe using a branch pipe connecting device, one end side of a cylindrical connection adapter is extrapolated to the existing pipe side end of the gate valve, and the connection adapter The other end side of the branch case is mounted on the existing pipe with the gate valve in a predetermined position, and the branch case is externally fitted on the existing pipe, and the branch case side end of the branch case is mounted. A first step of interpolating the other end side of the connection adapter into the part, and a fastener for fastening the flange parts of the divided body together with the split surface of the branch case positioned in a substantially horizontal direction Tighten the split bodies together, and A second step of firmly connecting the connection adapter and the connection adapter, a perforation device connected to the gate valve to perforate the peripheral wall of the existing pipe, and after completion of perforation by the perforation device, the perforation device is removed. And a third step of connecting the branch pipe to the gate valve.

  According to the branch pipe connection method according to the present invention, the split surface of the branch case connected to the flange is positioned in a substantially horizontal direction, and the connection between the branch case and the connection adapter fastens the flange portions of the split body of the branch case. Because it is done by tightening the fasteners to be connected, even if a heavy load due to ground fluctuation or secular change is applied, the connection location is not located in the opening direction, and it is difficult for the load to act on the fasteners. Can be surely and effectively prevented from leaking out from the connection location. In the present invention, since the cylindrical connection adapter is interposed between the branch case and the gate valve, the existing pipe and the branch pipe can be combined in various combinations without changing the size of the branch case as described above. Can be connected. As described above, according to the present invention, it is possible to reduce the number of branch cases while preventing leakage of fluid from the connection portion between the existing pipe and the branch pipe.

  In the above, the first step is to attach the gate valve to a predetermined position on the upper surface of the existing pipe with the other end side of the connection adapter facing downward, and after the first step, the branch case It is preferable that the dividing surface of the branch case is positioned in a substantially horizontal direction by integrally rotating the gate valve and the gate valve, and the process proceeds to the second step.

  According to the above method, the gate valve, the connection adapter, and the branch case are connected on the upper surface of the existing pipe, and by rotating them, the existing pipe can be perforated and the branch pipe can be subsequently connected. Therefore, when excavating a pit, it is only necessary to secure a space in the depth direction, and the space around the connection point necessary for installing the branch pipe connection device is reduced. Branch pipe connection work becomes possible. In addition, the time required for construction work such as pit formation work is shortened and work efficiency is increased.

In the above, when connecting the branch case and the connection adapter, the protrusion provided on the outer peripheral surface of the connection adapter is fitted into the recess formed at the end of the branch case on the gate valve side, and the recess A first inclined surface that is inclined to have an expanded diameter and opens outward, and a second inclined surface that is formed on the protrusion and is inclined toward the existing pipe side end of the connection adapter are in surface contact with each other. It is preferable to make it. Thereby, it is possible to easily perform the construction work by preventing the relative rotation of the branch case and the connection adapter while firmly connecting the branch case and the connection adapter.

  In the above, in the second step, the fastener is tightened to increase a contact area between the first inclined surface and the second inclined surface, and the first inclined surface presses the second inclined surface. Then, the inner protrusion rib wall of the concave groove formed to act in a direction to move the connection adapter away from the branch case and to fit a sealing material on the inner peripheral surface of the branch case near the end of the gate valve side. It is preferable that the connection adapter is brought into contact with an overhang portion formed on the existing pipe side end surface to stop the connection adapter from moving away from the branch case. According to such a configuration, in addition to the first inclined surface and the second inclined surface being in surface contact, the wedge effect is generated, so that the connection strength between the branch case and the connection adapter can be effectively increased. .

  Hereinafter, embodiments of a branch pipe connection device, a connection adapter, and a branch pipe connection method according to the present invention will be described with reference to the drawings, taking as an example the case of connecting a branch pipe to an existing water pipe. FIG. 1 is a front view showing an example of a gate valve and a connection adapter provided in a branch pipe connection device according to the present invention. FIG. 2 is a perspective view of the connection adapter, and FIG. 3 is a longitudinal sectional view of the connection adapter.

  The gate valve 2 has an end portion (existing pipe side end portion) directed to the left side in FIG. 1 connected to the connection adapter 7 and an end portion on the opposite side thereof is a receiving portion 2b having an enlarged diameter. The passage between the both ends is formed. The gate valve 2 has a built-in valve body (not shown) that allows a passage (not shown) to enter and exit the passage by rotating a jig (not shown) attached to the top 2c. Moreover, in this embodiment, the four claws 2a protrude from the outer peripheral surface of the existing pipe side end of the gate valve 2 at intervals in the circumferential direction. In the present invention, the number of claws 2a is not particularly limited.

  The connection adapter 7 is attached so as to be interposed between the gate valve 2 and a branch case 1 which will be described later. One end side which is the right side in FIG. 1 is extrapolated to the existing pipe side end of the gate valve 2, and the left side in FIG. The other end side is inserted into the end portion of the branch case 1 on the gate side. On the end face of one end of the connection adapter 7, a circular opening 7a having a diameter that allows the outer diameter of the existing pipe-side end of the gate valve 2 and circumferential positions at four locations on the outer periphery of the opening 7a. An opening 7b is formed which is arranged at an interval and can receive the claw 2a.

  Further, on the inner peripheral surface of the connection adapter 7, as shown in FIG. 3, an engagement wall 7c disposed between the openings 7b, an accommodation groove 7d for accommodating the claw 2a, and a sealing material 8 ( And an internal fitting groove 7e for fitting the internal fitting groove 7e (see FIG. 5). Moreover, the existing pipe side end surface of the connection adapter 7 has a concave shape along the outer peripheral surface of the existing pipe, which will be described later, and an overhang 7f is formed on the outer edge along the circumferential direction. Further, a pair of protrusions 7g are provided on the outer peripheral surface of the connection adapter 7 in the vertical direction of FIG. Each of the protrusions 7g is inclined in a direction downward toward the projecting portion 7f, and reference numeral 7g1 is an inclined surface of the protrusion 7g (corresponding to the second inclined surface).

  Hereinafter, a method of connecting a branch pipe to an existing pipe by the branch pipe connecting method according to the present invention will be described. First, one end of the connection adapter 7 is extrapolated and connected to the existing pipe side end of the gate valve 2. In the present embodiment, an example is shown in which the gate valve 2 and the connection adapter 7 are connected by a bayonet structure, and the existing pipe side end of the gate valve 2 is inserted into the connection adapter 7 as shown in FIGS. In this state, the connection adapter 7 is rotated relative to the gate valve 2 by a predetermined angle, so that the engagement wall 7c is placed on each of the claws 2a from the direction in which the gate valve 2 is pulled out (right direction in FIG. 5). It will be in the state which can be engaged.

  In the present embodiment, as shown in FIG. 4B, the pair of protrusions 7 g of the connection adapter 7 in the connected state are arranged in the vertical direction that is the moving direction of the valve body of the gate valve 2. Note that a structure that restricts the relative rotation between the gate valve 2 and the connection adapter 7 may be provided by providing a protrusion that can receive the claw 2a at a predetermined location of the housing groove 7d. According to the above, since the force in the axial direction acts due to the water pressure in the pipe, the claw 2a and the engaging wall 7c are firmly in close contact with each other, and therefore, the pipe does not rotate unexpectedly.

  Subsequently, as shown in FIG. 6, the gate valve 2 is mounted at a predetermined position on the upper surface of the existing pipe K with the other end of the connection adapter 7 facing downward. Since the gate valve 2 changes its circumferential position with respect to the existing pipe K in a subsequent process, this state is temporarily placed. Usually, since the existing pipe K is buried in the soil, the peripheral part of the location where the branch pipe is connected is excavated to form a pit. In this embodiment, since the existing pipe side end surface of the connection adapter 7 forms a concave shape along the outer peripheral surface of the existing pipe K, temporary placement is stable, and workability can be improved.

  Next, as shown in FIG. 7, the branch case 1 is externally fitted and mounted from below the existing pipe K so as to hold the existing pipe K, and is attached to the end of the branch case 1 on the gate side. The other end of the connection adapter 7 is inserted (the above process corresponds to the first process). Thus, the connection adapter 7 is not flanged to the branch case 1. The branch case 1 has a split T-tube shape, and is composed of split bodies 1A and 1B that are split into left and right parts in FIG.

  FIG. 8 is an enlarged view of the main part of FIG. 7 and shows one side of the branch valve side end of the branch case 1. The end portion of the branch case 1 on the side of the gate valve is provided with a recess 1b (see FIG. 11) having an inclined surface 1b1 (corresponding to the first inclined surface) that is inclined outwardly and opens outward. . In this embodiment, the recessed part 1b is formed in each of the division bodies 1A and 1B on the left and right of FIG. 7, and the projection 7g is fitted into the pair of recessed parts 1b. The inclined surface 7g1 of the protrusion 7g and the inclined surface 1b1 of the recess 1b are provided so as to be slidable in surface contact with each other, but it is not necessary to be in surface contact at this stage.

  Thus, since the projection 7g is fitted in the recess 1b, the relative rotation between the branch case 1 and the connection adapter 7 can be prevented, and the construction work can be easily performed. The flange portions of the split bodies 1A and 1B of the branch case 1 are fastened by a fastener 3 including a bolt 3a and a nut 3b. At this stage, the bolt 3a and the nut 3b are temporarily fixed without being sufficiently tightened. deep. As will be described later, when the fastener 3 is further tightened, it is connected in a watertight manner by the sealing material 4 built in the split end portion and the sealing material 5 fitted on the outer peripheral surface of the connection adapter 7 to branch. Case 1 and connection adapter 7 are firmly connected.

  Next, as shown in FIG. 9, the split case 1 and the gate valve 2 are integrally rotated about 90 ° in the clockwise direction in FIG. To be located. At this time, it is preferable to place the block 6 so as to support the leg 1a of the branch case 1 and the overhanging portion of the receiving portion 2b of the gate valve 2. In addition, the description of the leg 1a and the board 6 is omitted except for FIG.

  Due to this rotation, the split direction of the branch case 1, which has been left and right in FIG. 7, is moved up and down, the split surface of the branch case 1 is positioned in a substantially horizontal direction, And almost parallel. For this reason, even when the branch case 1 and the connection adapter 7 are not flange-connected, after connecting the branch pipe to the existing pipe K, even if a large load suddenly or gradually acts on those connection locations. Since the connection location is not located in the opening direction and the load is unlikely to act on the fastener such as the bolt 3a, it is possible to reliably and effectively prevent the fluid inside the pipe from leaking from the connection location.

  Further, in this embodiment, the diameter of the branch pipe is smaller than that of the existing pipe K, and the size of the branch case 1 does not correspond to the gate valve 2 as can be seen from FIG. The two can be connected by the connection adapter 7 interposed between the two. By using such a connection adapter 7, the existing pipe K and the branch pipe can be connected in various combinations without changing the size of the branch case 1, so that the number of the branch cases 1 can be reduced.

  Furthermore, in this embodiment, when excavating the periphery of the existing pipe K to form a pit, the pit is formed somewhat deep, and the gate valve 2 and the branch case 1 connected to the connection adapter 7 are connected to the existing pipe K. The branch pipe connection work can be performed by attaching to and rotating as described above. For this reason, the present invention is applicable even in a place where a wide surrounding space cannot be secured, for example, an existing building is present in the vicinity, and the time required for the pit formation work can be shortened and work efficiency can be improved.

  Subsequently, the fastener 3 is further tightened to increase the connection strength between the branch case 1 and the connection adapter 7. At this time, as shown in FIGS. 10 and 11, the inclined surface 1 b 1 of the concave portion 1 b of the branch case 1 is in surface contact with the inclined surface 7 g 1 of the protrusion 7 g of the connection adapter 7 at two locations in the upper and lower portions. The sealing material 5 has a closed circular shape, and is fitted in a recessed groove formed on the inner peripheral surface of the branch case 1 near the gate valve end. When the fastener 3 is further tightened, as shown in FIGS. 12 and 13, the contact area between the inclined surface 1b1 and the inclined surface 7g1 increases at two locations, and the inclined surface 1b1 presses the inclined surface 7g1. This acts in a direction to move the connection adapter 7 away from the branch case 1.

  Then, as shown in FIGS. 14 and 15, the fastener 3 is further tightened to firmly connect the branch case 1 and the connection adapter 7 (corresponding to the second step). At this time, the inclined surface 1b1 and the inclined surface 7g1 are in surface contact so as to maximize the contact area, the inclined surface 1b1 of the branch case 1 presses the inclined surface 7g1 of the connection adapter 7, and the connection adapter from the branch case 1 7 is moved away from the branch case 1 by contacting the inner projecting wall 1c of the recessed groove into which the sealing material 5 is fitted and the overhanging portion 7f of the connection adapter 7. And the fastening by the fastener 3 is completed. According to such a configuration, even if a large load is applied after connecting the branch pipe, the connection between the branch case 1 and the connection adapter 7 is strong, so that it is possible to effectively prevent the fluid from leaking.

  In the present invention, since the split surface of the branch case 1 is positioned in a substantially horizontal direction, the flange portions of the split bodies 1A and 1B are fastened in the vertical direction, and therefore a pair of protrusions in the concave portion 1b arranged in the vertical direction. By fitting 7g, the connection strength between the branch case 1 and the connection adapter 7 can be suitably secured.

  When there are other fastening locations of the branch case 1, they are fastened using bolts and nuts that are fasteners, and the water tightness of the branch case 1 attached to the existing pipe K is ensured. After the branch case 1 and the connection adapter 7 are firmly connected, a perforating device is connected to the receiving portion 2b of the gate valve 2, and the valve body of the gate valve 2 is retracted upward so that the interior of the gate valve 2 is communicated. After opening to a state, the surrounding wall of the predetermined location of the existing pipe K is pierced with a piercing device. Then, after the drilling is completed, the rotation of the hole saw built in the drilling device is stopped, the drilling device is removed, and instead the end of the branch pipe is inserted into the receiving port 2b to terminate the connection. A usable state is set (corresponding to the third step).

[Another embodiment]
(1) In the above-described embodiment, when the branch case 1 and the connection adapter 7 are firmly connected, the fastener 3 is tightened, and the inclined surface 1b1 of the recess 1b of the branch case 1 and the projection 7g of the connection adapter 7 Although the contact area with the inclined surface 7g1 is increased, the inclined surface 1b1 presses the inclined surface 7g1, and the connection adapter 7 is moved away from the branch case 1 to be connected. In order to increase the connection strength with the adapter 7, bolts 10 may be interposed as shown in FIGS.

  That is, as shown in FIGS. 16A to 16C, a bolt hole in which a female screw is formed is formed at a position between the recessed groove into which the sealing material 5 is inserted and the inclined surface 1b1. By screwing the bolts 10 into the connection, the connection between the branch case 1 and the gate valve 2 is further strengthened. In this case, as the fastener 3 is tightened, the inclined surface 1b1 presses the inclined surface 7g1 and the inner protruding wall 1c of the branch case 1 and the connection adapter 7 as shown in FIGS. After the contact with the overhanging portion 7f stops, as shown in FIG. 16 (d), the bolt 10 may be screwed and screwed.

  The screw 10 may be screwed at one place or a plurality of places. Moreover, you may connect the volt | bolt 10 so that the connection adapter 7 may be acted in the direction away from the branch case 1 by pressing the inclined surface 7g1 of the protrusion 7g directly. However, when such a bolt 10 is interposed, it is not always necessary to adopt a configuration in which the inclined surface 1b1 presses the inclined surface 7g1 and acts to connect the connection adapter 7 away from the branch case 1 to connect. The branch case 1 and the connection adapter 7 may be connected by tightening the fastener 3 and screwing the bolt 10.

  (2) In the above-described embodiment, tap water is taken as an example of the fluid inside the pipe. However, the present invention is not limited to this, and can be applied to fluids such as various liquids and gases.

  (3) In the above-described embodiment, the example in which the gate valve 2 and the connection adapter 7 are connected by the bayonet structure is shown, but the present invention is not limited to this. For example, a male screw formed on the outer peripheral surface of the existing pipe side end of the gate valve 2 may be connected by screwing with a female screw formed on the inner peripheral surface of the connection adapter 7. The structure shown in FIG. 17 is also a preferred embodiment. In the example of FIG. 17, the gate valve 2 and the connection adapter 7 are connected via the sealing material 23, and a storage groove 22 for storing the lock ring 21 is formed on the inner peripheral surface of the connection adapter 7. When the withdrawal output acts on the gate valve 2, the lock ring 21 is pulled out of the projection 2d provided on the outer peripheral surface of the existing pipe side end of the gate valve 2 (rightward in FIG. 17). ) Can be engaged. In this case, it is not necessary to rotate the connection adapter 7 externally attached to the gate valve 2. Reference numeral 24 denotes a centering rubber for the lock ring 21.

  (4) In the above-described embodiment, an example in which the pair of protrusions 7g is provided on the outer peripheral surface of the connection adapter 7 is shown, but in the present invention, the number of the protrusions 7g is not particularly limited, and may be one or three or more. . However, considering that the split surface of the branch case 1 is positioned in a substantially horizontal direction and the flange portions of the split bodies 1A and 1B are fastened in the vertical direction, the connection strength between the branch case 1 and the connection adapter 7 is ensured. From this point of view, it is preferable that a pair of protrusions 7g that can be fitted in the recesses 1b arranged in the vertical direction are provided.

  (5) In the above-described embodiment, the example in which the gate valve 2 is connected to the branch pipe with the top portion 2c facing upward is shown. However, by changing the circumferential position of the projection 7g of the connection adapter 7, the gate valve 2 is changed. It is also possible to connect the branch valve 2 to the branch pipe in a tilted state, that is, in a state where the gate valve 2 is tilted and tilted around the axis so that the top portion 2c does not face upward. Thereby, since the height position of the top part 2c of the gate valve 2 is lowered, the amount of earth covering from the top part 2c to the ground can be appropriately obtained even when the existing pipe K buried in the shallow layer is targeted.

  (6) In the above-described embodiment, the example in which the connection adapter 7 is directly placed on the upper surface of the existing pipe has been shown. However, a material softer than the constituent material of the connection adapter 7 on the existing pipe side end face of the connection adapter 7. More preferably, a lining layer made of is formed and placed on the upper surface of the existing pipe through the lining layer. In this case, the operation | work which mounts the connection adapter 7 and the gate valve 2 on the upper surface of the existing pipe K can be stabilized. Moreover, since the clearance adjustment is facilitated by absorbing the tolerance of the pipe diameter of the existing pipe K, the mounting property to the existing pipe K is improved.

  (7) In the above-described embodiment, an example is shown in which the diameter drops from the existing pipe K toward the branch pipe (the pipe diameter decreases), but the diameter may drop from the branch pipe toward the existing pipe K. . In this case, a different diameter structure in which one end side of the connection adapter 7 has a large diameter and the other end side has a small diameter may be employed.

  (8) In the above-described embodiment, the example in which the dividing surface of the branch case 1 is positioned in the substantially horizontal direction by rotating the gate valve 2, the connection adapter 7, and the branch case 1 attached to the existing pipe K has been described. The present invention is not limited to this. For example, when attaching the branch case 1 to the existing pipe K, the dividing surface may be positioned in the substantially horizontal direction from the beginning. In this case, after mounting the divided body 1B below the existing pipe K, the gate valve 2 connected to the connection adapter 7 is mounted on the existing pipe K, and then the divided body 1A is mounted above the existing pipe K. The state shown in FIG. 9 is obtained.

The front view which shows an example of the gate valve and connection adapter with which the branch pipe connection apparatus which concerns on this invention is equipped Perspective view of connection adapter Vertical section of connection adapter Front view showing the connection adapter attached to the gate valve 4A is a cross-sectional view taken along arrow AA in FIG. Partial sectional view showing a state where a gate valve is mounted on an existing pipe Partial sectional view showing a state where a branch case is attached to an existing pipe 7 is an enlarged view of the main part of FIG. Partial sectional view showing the state where the branch case is rotated Partial sectional view showing a state in which the fastener is tightened BB arrow view of FIG. The fragmentary sectional view which shows the state which tightened the fastener further from the state of FIG. CC arrow view of FIG. Partial sectional view showing a state in which tightening by a fastener is completed DD arrow view of FIG. The figure explaining the modification of the connection structure of a branch case and a connection adapter The figure explaining the modification of the connection structure of a gate valve and a connection adapter Front view for explaining an example of a conventional branch pipe connection device Front view for explaining an example of a conventional branch pipe connection device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Branch case 1A, 1B Divided body 1b Recessed part 1b1 1st inclined surface 1c Inner protrusion wall 2 Gate valve 2a Claw 2d Projection part 3 Fastener 5 Sealing material 7 Connection adapter 7a Opening part 7b Opening part 7c Engagement wall 7f Overhang 7g Projection 7g1 Second inclined surface 8 Sealing material 21 Lock ring 22 Storage groove K Existing pipe

Claims (9)

A branch case made of a split body having a flange portion and watertightly mountable on an existing pipe, and a gate valve having a built-in valve body and connectable to the branch pipe, the branch pipe being connectable to the existing pipe In the branch pipe connecting device
A cylindrical shape interposed between the branch case and the gate valve, one end side of which is extrapolated to the existing pipe side end of the gate valve, and the other end side is inserted into the gate end of the branch case. Have a connection adapter,
In the split surface of the branch case, the flange portions of the split body are fastened by a fastener, the split surface is positioned in a substantially horizontal direction, and the branch case and the connection adapter are fastened by fastening the fastener. the connection is Do via the sealing material,
A recessed portion having a first inclined surface that is inclined in an enlarged diameter and opens outward is formed at the gate valve side end of the branch case, and an existing pipe side end of the connection adapter is formed on the outer peripheral surface of the connection adapter. A protrusion having a second inclined surface that is inclined in a downward direction toward the portion, and when the connection adapter is connected to the branch case, the protrusion is fitted into the recess, and the first inclined surface and the A branch pipe connecting device characterized in that the second inclined surface is in surface contact with each other. As the fastener is tightened, the contact area between the first inclined surface and the second inclined surface increases, the first inclined surface presses the second inclined surface, and the connection adapter extends from the branch case. A recess groove is formed on the inner peripheral surface of the branch case near the gate valve side end portion, and an inner protrusion that constitutes the recess groove is formed. 2. The branch according to claim 1 , wherein the strip wall comes into contact with an overhang portion formed on an existing pipe side end surface of the connection adapter so that the connection adapter can be stopped from moving away from the branch case. Pipe connection device One or a plurality of claws projecting from the outer peripheral surface of the existing pipe side end of the gate valve, and the connection adapter includes an opening for receiving the claw, and the claw received through the opening. The branch pipe connection device according to claim 1 or 2 , further comprising an engagement wall that can be engaged from a direction in which the gate valve is withdrawn, wherein the gate valve and the connection adapter are connected by a bayonet structure. A storage groove in which a lock ring is stored is formed on the inner peripheral surface of the connection adapter, and the lock ring is formed on a protrusion provided on the outer peripheral surface of the existing pipe side end of the gate valve. The branch pipe connecting device according to claim 1 , wherein the branch pipe connecting device is configured to be engageable from a pulling direction. It is interposed between a branch case that consists of a split body having a flange portion and can be attached to an existing pipe in a water-tight manner, and a gate valve that has a built-in valve body and can be connected to the branch pipe. While being extrapolated to the side end portion, the other end side forms a cylindrical body inserted into the branch valve side end portion of the branch case,
A protrusion that can be fitted into a recess formed at the gate valve side end of the branch case is provided on the outer peripheral surface, and the first inclined surface that is inclined outwardly to the protrusion and has an enlarged diameter is provided on the protrusion. The connection adapter in which the 2nd inclined surface which inclines in the direction which falls to the existing pipe side edge part which can carry out surface contact is formed. A branch pipe connecting device comprising a branch case made of a split body having a flange portion and capable of being watertightly attached to an existing pipe, and a gate valve having a built-in valve body and connectable to the branch pipe. In the branch pipe connection method for connecting to the existing pipe,
Extrapolate one end of the connection adapter in the form of a cylinder to the existing pipe side end of the gate valve, and attach the gate valve to a predetermined location of the existing pipe with the other end of the connection adapter facing the existing pipe And a first step of fitting and attaching the branch case to the existing pipe, and interpolating the other end side of the connection adapter at the gate end of the branch case.
With the split surface of the branch case positioned in a substantially horizontal direction, the split bodies are fastened using a fastener that fastens the flange portions of the split bodies, and the branch case and the connection adapter are tightened. A second step of connecting;
A third step of connecting a perforating device to the gate valve to perforate a peripheral wall of the existing pipe, removing the perforating device after completion of perforation by the perforating device, and connecting the branch pipe to the gate valve; A branch pipe connection method characterized by this. The first step is to attach the gate valve to a predetermined position on the upper surface of the existing pipe with the other end side of the connection adapter facing downward.
After the first step, claim said substantially are positioned horizontally split surface of the branch casing by rotating integrally with the branch casing and the partition valve, the process proceeds to the second step 6 The branch pipe connection method described. When connecting the branch case and the connection adapter, a protrusion provided on the outer peripheral surface of the connection adapter is fitted into a recess formed at the end of the branch case on the gate valve side, and the extension of the recess is provided. a first inclined surface that opens outwardly inclined径状, claim that the formed on the protrusion and the second inclined surface and the surface contact with each other inclined in the direction down towards the existing pipe end of the connection adapter The branch pipe connection method according to 6 or 7 . In the second step, the fastener is tightened to increase a contact area between the first inclined surface and the second inclined surface, and the first inclined surface presses the second inclined surface, In addition to acting in the direction away from the connection adapter from the branch case, the inner ridge wall of the concave groove formed to fit the seal material on the inner peripheral surface near the gate valve side end portion of the branch case, and The branch pipe connection method according to claim 8 , wherein an extension portion formed on an existing pipe side end face of the connection adapter is brought into contact with the branch adapter to stop the connection adapter from moving away from the branch case.

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