JP5618722B2 - Sealing members, pipe fittings and water intake piping - Google Patents

Description

  The present invention relates to a seal member used for a pipe joint in which an insertion port is inserted into a receiving port, a pipe joint provided with the seal member, and a water intake pipe formed by joining a plurality of pipes with pipe joints.

  Conventionally, a so-called slip-on type pipe joint is known as a kind of pipe joint for joining pipes such as cast iron pipes. As shown in FIG. 9 (a), this pipe joint 51 has an insertion port 55 formed in the other pipe 52 inserted into a reception port 54 formed in one pipe 52 to be joined to each other. Between the inner periphery of 54 and the outer periphery of the insertion port 55, water is stopped by an annular seal member 56.

  The seal member 56 is made of rubber, is fitted into a groove 57 formed on the inner periphery of the receiving port 54, and is compressed between the inner periphery of the receiving port 54 and the outer periphery of the insertion port 55. . As a result, the water (fluid) in the pipe 52 is stopped by the seal member 56, so that the water in the pipe 52 does not leak out between the inner periphery of the receiving port 54 and the outer periphery of the insertion port 55. Is prevented.

  Such a slip-on type pipe joint 51 is described in, for example, Patent Document 1 below.

4-133092

  In the above conventional format, the pipe 58 is configured by joining a plurality of pipes 52 with the pipe joint 51 as described above, and the pipe 58 may be installed in the ground. In this case, as shown in FIG. 9B, an external pressure (external water pressure) may act on the pipe joint 51 due to the water pressure of the groundwater 59 outside the pipe 58. When external pressure acts in this way, it becomes impossible to reliably stop water between the inner periphery of the receiving port 54 and the outer periphery of the insertion port 55, and the inner end of the receiving port 54 from the end opening 60 of the receiving port 54. There is a problem that the groundwater 59 that has entered between the periphery and the outer periphery of the insertion port 55 leaks into the pipe 52 through the space between the inner periphery of the receiving port 54 and the outer periphery of the seal member 56 due to external pressure. For example, when the groundwater 59 is contaminated and clean water is stored in the pipe 58, the contaminated groundwater 59 may be mixed into the clean water in the pipe 58.

  The present invention provides a seal member for a pipe joint, a pipe joint, and a water intake pipe capable of reliably stopping water between the inner periphery of the receiving port and the outer periphery of the seal member even when an external pressure acts on the pipe joint. For the purpose.

In order to achieve the above object, according to the first aspect of the present invention, an insertion port formed in the other tube is inserted into a receiving port formed in one tube joined to each other ,
A pipe joint between the inner periphery of the receiving port and the outer periphery of the insertion port is water-stopped by a sealing member,
The seal member has an annular valve portion made of an elastic material sandwiched between the inner periphery of the receiving port and the outer periphery of the insertion port and compressed in the radial direction,
The valve part is provided with a lip part on the entire outer periphery side,
The lip portion has a first pressure receiving surface that receives a radially outward external pressure that acts between the inner periphery of the receiving port and the outer periphery of the insertion port from the outside of the pipe joint ,
Between the inner periphery of the receiving port and the seal member, a gap surrounded by the inner periphery of the receiving port, the seal member and the first pressure receiving surface is formed,
When external fluid enters between the inner periphery of the receiving port and the outer periphery of the seal member and enters the gap, the external pressure is received by the first pressure receiving surface .

  According to this, when an external pressure is applied to the pipe joint, the radially outward pressure acting between the inner periphery of the receiving port and the outer periphery of the insertion port is received by the first pressure receiving surface of the lip portion from the outside of the pipe joint. Is pushed outward in the pipe diameter direction and is pushed against the inner periphery of the receiving port. Thereby, it is possible to reliably stop water (self-seal) between the inner periphery of the receiving port and the outer periphery of the seal member with respect to the external pressure.

In the pipe joint according to the second aspect of the invention, the valve portion has a second pressure receiving surface that receives the internal pressure acting on the pipe joint at the end on the back side of the receiving port,
The internal pressure received by the second pressure receiving surface generates an outward pressing force in the tube diameter direction on the outer periphery of the valve portion, and an inward pressing force in the tube diameter direction on the inner periphery of the valve portion. It is.

  According to this, when an internal pressure acts on the pipe joint, the internal pressure is received by the second pressure receiving surface of the valve portion, and outward and inward pressing forces are generated in the valve portion. For this reason, the outer periphery of the valve portion is pressed against the inner periphery of the receiving port, and the inner periphery of the valve portion is pressed against the outer periphery of the insertion port. Thereby, it is possible to reliably stop water (self-seal) between the inner periphery of the receiving port and the outer periphery of the insertion port with respect to the internal pressure.

In the pipe joint according to the third aspect of the invention, a heel portion that is fitted in a fitting groove formed on the inner periphery of the receiving port and holds the seal member in the mounting position is formed integrally with the valve portion,
The heel part is located closer to the receiving opening than the valve part.
The cross-sectional shape of the end portion on the rear side of the valve portion is an arc shape.

  According to this, by inserting the heel portion of the seal member into the insertion groove, the seal member is held at a predetermined mounting position in the receiving port, and in this state, the insertion port is inserted into the receiving port. At this time, the insertion port is inserted on the inner peripheral side of the seal member and the valve portion is expanded in diameter by the insertion port, whereas the lip portion is provided on the outer peripheral side of the valve portion. Power does not increase significantly.

The fourth invention is a seal member that is provided in the pipe joint according to any one of the first to third inventions.

The water intake pipe in the fifth invention is disposed in a vertical hole in which a plurality of pipes joined by the pipe joint according to any one of the first to third inventions are dug in the ground. Is.
According to this, it is possible to prevent external ground water from leaking from the pipe joint into the pipe and ground water inside the pipe from leaking from the pipe joint to the outside.

  As described above, according to the present invention, it is possible to reliably stop water between the inner periphery of the receiving port and the outer periphery of the seal member against external pressure. Moreover, it is possible to reliably stop water between the inner periphery of the receiving port and the outer periphery of the insertion port against the internal pressure. Thereby, it is possible to prevent external fluid from leaking from the pipe joint into the pipe and from leaking from the pipe joint to the outside.

It is sectional drawing of the piping for water intake in the 1st Embodiment of this invention. It is sectional drawing of the pipe joint of intake piping same as the above. It is a figure of the sealing member provided in a pipe joint similarly, (a) is a side surface, (b) shows the cross section of (a). It is an enlarged sectional view of a sealing member. It is sectional drawing of a pipe joint and shows the state in which internal water pressure is acting on a sealing member. It is sectional drawing of a pipe joint and shows the state where the external water pressure is acting on the sealing member. FIG. 4 is a cross-sectional view of the pipe joint, showing a state where the seal member is mounted in the receiving port and the insertion port starts to be inserted into the receiving port. It is an expanded sectional view of the sealing member in the 2nd Embodiment of this invention. It is sectional drawing of the conventional pipe joint.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
First, a first embodiment will be described with reference to FIGS.

  As shown in FIG. 1, reference numeral 1 denotes a vertical hole type well excavated in the ground 2, and a water intake pipe 3 is arranged in a vertical posture inside the vertical hole 6. A pumping pipe 4 for pumping up groundwater is inserted into the water intake pipe 3, and a pump 5 is connected to the pumping pipe 4. The intake pipe 3 is constituted by joining a plurality of pipes 11 with pipe joints 12. A water intake 7 having a net or the like is formed at the lower end of the water intake pipe 3.

The pipe joint 12 has the following configuration.
As shown in FIG. 2, each tube 11 has a receiving port 15 at one end and an insertion port 16 at the other end. The insertion port 16 of the other tube 11 is inserted into the receiving port 15 of the one tube 11 joined to each other, and water is stopped between the inner periphery of the receiving port 15 and the outer periphery of the insertion port 16 by the seal member 17. .

  As shown in FIGS. 3 and 4, the seal member 17 is an annular member made of an elastic material such as rubber, and connects the valve portion 18, the heel portion 19, and the valve portion 18 and the heel portion 19. And the connecting portion 20 to be integrated. The heel portion 19 has a rectangular cross section as shown in FIG. 4 and is positioned closer to the opening portion 23 of the receiving port 15 than the valve portion 18 as shown in FIG. The seal member 17 is held in a predetermined mounting position by being fitted in the fitting groove 27 formed in the above. The inner peripheral surface of the heel portion 19 is parallel to the tube axis.

  As shown in FIG. 5, the valve portion 18 is stored in a storage groove 28 formed on the inner periphery of the receiving port 15, and the bottom surface of the storage groove 28 that is a part of the inner periphery of the receiving port 15 and the insertion port 16. It is sandwiched between the outer periphery and compressed in the radial direction. In addition, as shown in FIG. 4, in the state which removed the seal member 17 from the pipe joint 12, the cross-sectional shape of the receptacle back | inner side edge part of the valve | bulb part 18 bulges in semicircle shape (an example of circular arc shape). Has been.

  As shown in FIGS. 4-6, the valve | bulb part 18 is provided with the lip | rip part 24 over the perimeter on the outer peripheral side. The lip portion 24 receives a distal end 24a that protrudes outward in the radial direction of the tube and protrudes toward the heel portion 19, and receives external water pressure P1 (an example of external pressure that is outward in the radial direction) that acts radially outward and obliquely. 1 pressure receiving surface 24b is provided over the entire circumference. In addition, between the heel part 19 and the lip | rip part 24, the recessed part 25 hollow inward in the pipe radial direction is formed over the perimeter.

  Between the fitting groove 27 and the storage groove 28 in the tube axis direction, a protrusion 29 protruding inward in the tube diameter direction is formed over the entire circumference, and the protrusion 29 is inserted into the recess 25. . Note that a space 26 surrounded by the bottom surface of the recess 25, the protrusion 29, and the first pressure receiving surface 24 b is formed between the inner periphery of the receiving port 15 and the seal member 17. As shown in FIG. 5, the first pressure receiving surface 24 b is inclined outward in the pipe diameter direction toward the opening 23 side of the receiving port 15 in a state where the seal member 17 is mounted in the pipe joint 12.

Further, the valve portion 18 has a second pressure receiving surface 18 a that receives an internal water pressure P <b> 2 (internal pressure) acting on the pipe joint 12 at the end on the back side of the receiving port.
Further, the connecting portion 20 has a tapered surface 20 a on the inner periphery that extends from the inner periphery of the heel portion 19 to the inner periphery of the valve portion 18.

Hereinafter, the operation of the above configuration will be described.
As shown in FIG. 1, when the pump 5 is operated and the groundwater 32 inside the intake pipe 3 of the well 1 is pumped up from the pumping pipe 4, the water level of the groundwater 32 inside the intake pipe 3 gradually decreases. However, a water level difference H occurs between the groundwater 32 inside the intake pipe 3 and the outside groundwater 33, and an external water pressure (external pressure) larger than the internal water pressure (internal pressure) may act on the pipe joint 12.

  When such an external water pressure acts, as shown in FIG. 6, the groundwater 33 outside the pipe receives the outer periphery of the seal member 17 from the inner periphery of the opening 23 of the receiving port 15 and the outer periphery of the insertion port 16. Passing between the inner periphery of the mouth 15 and entering the gap portion 26. Thus, the radially outward and oblique external water pressure P1 generated (acted) in the gap portion 26 is received by the first pressure receiving surface 24b of the lip portion 24, and the lip portion 24 faces outward in the tube radial direction. It is pushed and pressed against the bottom surface (receiving port inner periphery) of the storage groove 28 of the receiving port 15. Thereby, water can be reliably stopped (self-sealed) between the inner periphery of the receiving port 15 and the outer periphery of the seal member 17 with respect to the external water pressure P1.

  On the contrary, when an internal water pressure larger than the external water pressure acts on the pipe joint 12 due to a difference in water level between the groundwater 32 inside the intake pipe 3 and the groundwater 33 outside, as shown in FIG. This internal water pressure P2 is received by the second pressure receiving surface 18a of the valve portion 18. Due to the internal water pressure P2, an outward pressing force F1 in the pipe radial direction is generated on the outer periphery of the valve portion 18, and the internal pressure of the valve portion 18 is increased. An inward pressing force F2 in the pipe radial direction is generated around the circumference. Therefore, the outer periphery of the valve portion 18 is pressed against the bottom surface (receiving port inner periphery) of the receiving groove 28 of the receiving port 15, and the inner periphery of the valve portion 18 is pressed against the outer periphery of the insertion port 16. Thereby, water can be reliably stopped (self-sealed) between the inner periphery of the receiving port 15 and the outer periphery of the insertion port 16 with respect to the internal water pressure P2.

  In this way, even when at least one of the external water pressure P1 and the internal water pressure P2 acts on the pipe joint 12, the water in the pipe joint 12 can be reliably stopped. It is possible to prevent groundwater 33 outside the pipe 3 from leaking from the pipe joint 12 to the inside of the water intake pipe 3, and ground water 32 inside the water intake pipe 3 from the pipe joint 12 to the water intake pipe 3. It is possible to prevent leakage to the outside.

  Further, when the pipes 11 are joined together, as shown in FIG. 7, the valve member 18 of the seal member 17 is housed in the housing groove 28, and the heel portion 19 is fitted into the fitting groove 27. It is held at a predetermined mounting position in the tube axis direction in the receiving port 15. In this state, the insertion slot 16 is inserted into the receiving slot 15. At this time, the insertion port 16 is inserted into the inner peripheral side of the seal member 17, and the valve portion 18 is expanded in diameter by the insertion port 16. On the other hand, since the lip portion 24 is provided on the outer peripheral side of the valve portion 18, the insertion force of the insertion port 16 does not increase significantly, and the joining operation can be easily performed.

(Second Embodiment)
Next, in the second embodiment, as shown in FIG. 8, the seal member 17 is disposed on the inner periphery of the valve portion 18 from the inner peripheral end of the heel portion 19 through the inner periphery of the connecting portion 20. And has a tapered surface 40 extending to the end.

According to this, the same operation and effect as the first embodiment can be obtained.
In each of the above embodiments, as shown in FIG. 1, the seal member 17 is provided in the pipe joint 12 of the water intake pipe 3 of the well 1, but is not limited to the water intake pipe 3 of the well 1. Alternatively, it may be provided in the pipe joint 12 of the pipe where the external pressure may act.

  In each of the above embodiments, as shown in FIG. 4, the cross-sectional shape of the end portion on the back side of the valve portion 18 is formed to bulge into a semicircular shape as an example of an arc shape. The term includes not only a shape in which a circle is exactly halved but also a shape in which a circle is substantially (substantially) halved. Moreover, it is not limited to the semicircular shape, and other examples of the arc shape include those formed by bulging into a semielliptical shape. The semi-elliptical shape includes not only a shape in which the ellipse is exactly halved but also a shape in which the ellipse is substantially (substantially) halved.

3 Pipe 11 for water intake Pipe 12 Pipe joint 15 Receiving port 16 Inserting port 17 Seal member 18 Valve portion 18a Second pressure receiving surface 19 Heel portion 23 Receiving port opening 24 Lip portion 24b First pressure receiving surface 27 Fitting groove F1 outward Pressure F2 Inward pressure P1 External water pressure (external pressure)
P2 Internal water pressure (internal pressure)

Claims (5)

The insertion port formed in the other tube is inserted into the receiving port formed in one tube joined together ,
A pipe joint between the inner periphery of the receiving port and the outer periphery of the insertion port is water-stopped by a sealing member,
The seal member has an annular valve portion made of an elastic material sandwiched between the inner periphery of the receiving port and the outer periphery of the insertion port and compressed in the radial direction,
The valve part is provided with a lip part on the entire outer periphery side,
The lip portion has a first pressure receiving surface that receives a radially outward external pressure that acts between the inner periphery of the receiving port and the outer periphery of the insertion port from the outside of the pipe joint ,
Between the inner periphery of the receiving port and the seal member, a gap surrounded by the inner periphery of the receiving port, the seal member and the first pressure receiving surface is formed,
A pipe joint characterized in that external fluid is received at the first pressure receiving surface by external fluid entering between the inner periphery of the receiving port and the outer periphery of the seal member and entering the gap . The valve portion has a second pressure receiving surface that receives an internal pressure acting on the pipe joint at the end on the back side of the receiving port,
Due to the internal pressure received at the second pressure receiving surface, an outward pressing force in the tube radial direction is generated on the outer periphery of the valve portion, and an inward pressing force in the tube radial direction is generated on the inner periphery of the valve portion. The pipe joint according to claim 1. A heel portion that is fitted in a fitting groove formed on the inner periphery of the receiving port and holds the seal member in the mounting position is formed integrally with the valve portion,
The heel part is located closer to the receiving opening than the valve part.
The pipe joint according to claim 1 or 2, wherein a cross-sectional shape of the end portion on the back side of the valve portion is an arc shape. A seal member provided in the pipe joint according to any one of claims 1 to 3. A pipe for intake water, wherein a plurality of pipes joined by the pipe joint according to any one of claims 1 to 3 are arranged in a vertical hole dug in the ground.

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