JP2010014246A - Joint for flexible pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint for a flexible pipe capable of inspecting gas leakage only by incorporating an O-shaped waterproof packing. <P>SOLUTION: A clearance between the inner periphery of a socket part 3 of a joint body 5 and the outer periphery of a push ring 7, is sealed by the O-shaped waterproof packing 29. A selectively permeable member 26 permeating gas without permeating a solid and liquid, is integrally embedded in the packing axis direction in several places in the circumferential direction of the O-shaped waterproof packing 29. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a joint for a flexible pipe for inserting and connecting a flexible pipe for gas such as gas, and more particularly to an improvement of a joint for flexible pipe that enables a gas leak inspection.

  As this type of joint for flexible pipes, for example, a joint body and a nut (push wheel) that is screwed into a female thread of a receiving portion of the joint body are provided, and a through hole is provided in the joint body or the nut. The gas is sealed with a selectively permeable member having a function of transmitting a gas such as water vapor but not a solid such as dust or liquid such as water or mist. According to this, when a nail is accidentally driven into the flexible pipe during construction, the gas leaked from the nail-punched portion passes through the gap between the metal corrugate pipe of the flexible pipe and the synthetic resin layer covering the outer periphery. It moves in the direction of the pipe axis and reaches the inside of the joint to which the flexible pipe is connected. In the joint, since a through hole communicating with the outside of the joint is provided in the joint main body or the nut, the gas leaking through the through hole is positively discharged to the outside. At this time, since the through hole is closed with a selectively permeable member, the leaked gas is actively permeated, while the solid (such as dust) and liquid (such as water and mist) permeate into the joint. I can stop. As described above, at the time of leak inspection, this leak can be reliably detected so that a nailing mistake or the like can be known (see, for example, Patent Document 1).

  Further, the flexible pipe joint is provided with an O-type waterproof packing (watertight O-ring) at the rear end of the nut's external thread, and the O-type waterproof packing is provided between the outer periphery of the nut and the inner periphery of the receiving portion of the joint body. The waterproof seal.

Japanese Patent Laying-Open No. 2005-321103 (for example, FIGS. 2 and 3)

  However, in the above flexible pipe joint, as a measure for detecting gas leakage, a special process of providing a through hole in the joint body or nut and a process of fitting a selectively permeable member into the through hole are required. Increase. In addition, the selectively permeable member is made of a material such as a sheet material including a continuous porous film formed from a tetrafluoroethylene resin powder, has no elasticity, and is incompressible. There is also a problem that a gap is easily generated between the outer periphery of the conductive member and liquid such as water or mist easily enters the joint body through the gap.

  The present invention has been made to solve such problems, and the object of the present invention is to provide an O-type waterproof packing for waterproof sealing between the push ring and the joint body as described above. To provide a flexible pipe joint that enables a gas leak inspection only by incorporating an O-type waterproof packing by providing a selective permeability for selectively transmitting gas to the O-type waterproof packing itself. .

  The present invention will be described with reference to the reference numerals attached to FIGS. 1 to 4 to facilitate understanding of the contents of the invention as described in claim 1. , A push ring 7 inserted into the receiving portion 3, a flexible tube 2 inserted into the receiving portion 3 from the push ring 7 and covering the outer periphery of the metal corrugate tube 2 a with the synthetic resin layer 10, and the receiving portion 3. Seal rubber that seals the gap between the outer periphery near the tip and the inner periphery of the receiving port 3 that is not covered with the synthetic resin layer 10 of the flexible tube 2 a inserted into the receiving port 3 and is exposed. 6 and an O-type waterproof packing that is fitted in a waterproof packing groove 28 provided on the inner periphery of the receiving portion 3 or the outer periphery of the press ring 7 and seals a gap between the inner periphery of the receiving portion 3 and the outer periphery of the press ring 7 29, the circumferential direction of the O-type waterproof packing 29 A selectively permeable member 26 that allows gas to permeate but does not permeate solids or liquids is integrally embedded in the packing axial direction, and the selectively permeable member 26 exposed to the front and rear end faces 29b and 29c of the O-type waterproof packing 29 is provided. The front and rear end faces 26a and 26b are arranged in the waterproof packing groove 28 and the front and rear end faces 29b and 29c of the O-type waterproof packing 29 so as to communicate with a gap 33 between the outer periphery of the push wheel 7 and the inner periphery of the receiving portion 3. It is characterized by facing the gaps 32a and 32b formed between the two.

  According to the above configuration, the gas leaked from the nailing portion or the like of the metal corrugate tube 2a of the flexible pipe 2 during the gas leak inspection (the enclosed air at the time of the leak inspection) is the metal corgate pipe 2a of the flexible pipe 2 and the synthetic resin. It reaches the inside of the joint body 5 through the gap between the layer 10 and the gap 33 between the outer periphery of the pusher wheel 7 on the front side of the O-type waterproof packing 29 and the inner periphery of the receiving portion 3 and the waterproof packing groove 28. A gap 32b between the inside of the waterproof packing groove 28 and the rear end face 29c of the O-type waterproof packing 29, through the gap 32a between the inner side and the front end face 29b of the O-type waterproof packing 29. Further, it is positively discharged to the outside through a gap 33 between the outer periphery of the push ring 7 on the rear side of the O-type waterproof packing 29 and the inner periphery of the receiving port 3. As a result, leakage can be reliably detected.

  When the permselective member 26 is integrally embedded in the O-type waterproof packing 29, a through hole is specially provided in the joint body or the nut (push wheel) as in the above-described conventional example, or the permselective property is selectively transmitted through the through hole. It is possible to obtain a joint for a flexible pipe that enables a gas leak inspection by a few processes that incorporate only the O-type waterproof packing 29 without fitting a member.

  In the flexible pipe joint according to claim 1, as described in claim 2, the selectively permeable member 26 is a sheet material including a continuous porous membrane formed by molding tetrafluoroethylene resin powder, or polyethylene, polypropylene, A porous material having continuous pores formed from a thermoplastic resin powder such as polymethyl acrylate can be used.

  The flexible pipe joint according to claim 1 or 2 is provided with a plurality of vent holes 29a in the circumferential direction of the O-type waterproof packing 29 so as to penetrate in the packing axial direction. A configuration in which a pin-shaped selectively permeable member 26 is press-fitted into 29a can be employed. According to this, the inner periphery of the vent hole 29a of the O-type waterproof packing 29 is in close contact with the outer periphery of the selectively permeable member 26 due to the elasticity of the O-type waterproof packing 29 itself. Even in the case of being made of a compressible material, there is no gap between the inner periphery of the vent hole 29a of the O-type waterproof packing 29 and the outer periphery of the selectively permeable member 26, and the O-type waterproof packing 29 is waterproof. Can be secured.

  According to the present invention, the O-type waterproof packing enables gas leakage inspection while ensuring waterproofness. Therefore, a flexible pipe joint that enables gas leakage inspection can be easily assembled with few man-hours.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a half cutaway cross-sectional view showing a flexible pipe joint according to an embodiment of the present invention in a state before insertion of the flexible pipe, and FIG. 2 is a half cutout cross section of the flexible pipe joint shown in the state of being inserted into the flexible pipe. FIG. 3 is a half cutaway cross-sectional view of the joint for the flexible pipe shown in a state after completion of insertion of the flexible pipe, FIG. 4A is a cross-sectional view of the half cutout of the seal rubber, and FIG. 3B is a rear view of the seal rubber. 5C is a side view of the seal rubber, FIG. 5A is a front view of the O-type waterproof packing, FIG. 5B is a cross-sectional view taken along line AA in FIG. 5A, and FIG. 6 is an O-type waterproof packing in FIG. It is an expanded sectional view of a part.

  As shown in FIG. 1, the joint 1 for flexible pipes which concerns on this invention forms the receiving part 3 which receives the front-end | tip part of the metal flexible pipe 2 in one end part, and has the external thread 4 for a connection in the outer periphery of the other end part. A formed joint body 5, a seal rubber 6 accommodated inside the receiving port 3 of the joint body 5, a push ring 7 inserted into the receiving port 3, and the like are provided.

  As shown in FIG. 1, the flexible tube 2 is composed of vinyl chloride or the like on the outer periphery of a metal corrugate tube 2a in which crests 8 and troughs 9 extending in the entire circumferential direction are alternately arranged in the tube axis direction. Covered with a resin layer 10.

  As shown in FIG. 1, a large-diameter hole 11, a medium-diameter hole 12, and a small-diameter hole 13 are sequentially provided in the receiving portion 3 of the joint body 5 from the inlet side (rear side) to the inner back side (front side). It is formed in a continuous form. A stopper portion 14 projects radially inward from the inner back end of the small diameter hole 13. A first taper 15 is formed between the small diameter hole 13 and the medium diameter hole 12 so as to narrow toward the small diameter hole 13, and a second taper 16 is formed between the medium diameter hole 12 and the large diameter hole 11. It is formed in a narrowed shape toward the medium diameter hole 13.

As shown in FIGS. 4A to 4C, the seal rubber 6 includes a cylindrical front side barrel portion 6a having an inner diameter substantially the same as the outer diameter of the peak portion 8 of the metal corrugate tube 2a, and the front side barrel. A pipe end receiving portion 6b projecting inwardly at the front end of the portion 6a, an annular sealing action portion 6c projecting outward at the rear end portion of the front body portion 6a, and a rearward connection from the seal action portion 6c A rear barrel portion 6d having an inner diameter larger than the inner diameter of the front barrel portion 6a, and a peak portion of the metal corrugate tube 2a that is connected to the rear end portion of the rear barrel portion 6d and is smaller than the inner diameter of the rear barrel portion 6d. And a retaining claw 6e having an inner diameter larger than the outer diameter of 8 and an outer diameter larger than the outer diameter of the rear body portion 6d.
The front side barrel portion 6a, the sealing action portion 6c, and the rear side barrel portion 6d are formed of NBR, SBR, EPDM, or the like. The tube end receiving portion 6b is formed of the same material or different material as the front side barrel portion 6a, the sealing action portion 6c, the rear side barrel portion 6d, and the like, and a reinforcing cored bar 6f such as a brass washer is embedded and molded.
The retaining claw portion 6e is formed in a partial arc shape with a metal material such as brass or hard resin harder than the front barrel portion 6a, the sealing action portion 6c, and the rear barrel portion 6d, and a plurality of these are formed on the rear barrel portion. 6d is integrally formed at a predetermined interval in the circumferential direction of the rear end portion. At the corner where the outer periphery and rear end surface of the retaining claw 6e intersect, a taper 25 having a rearward constriction is formed.

  As shown in FIG. 1, the seal rubber 6 has the tube end receiving portion 6b and the front body portion 6a positioned in the small diameter hole 13 and the sealing action portion 6c in the middle before the flexible tube 2 is inserted (initial state). While being located in the diameter hole 12, the retaining claw 6 e is accommodated and disposed so as to be located in the large diameter hole 11.

  As shown in FIG. 1, a tip latch member 17 is attached to the stopper portion 14 in the joint body 5. The tip latching member 17 has a C-shaped ring portion 17a that can freely expand and contract, and a resiliently deformable check claw 17b that protrudes from several locations on the inner diameter portion of the ring portion 17a. Etc. are formed. Then, the tip latching member 17 is engaged with the circumferential groove 14a provided on the outer diameter side of the stopper portion 14 while the ring portion 17a is overlapped with the stopper portion 14 and the reverse portion 17a is reversed. The pawl 17 b is attached to the stopper portion 14 so as to protrude into the small diameter hole 13.

As shown in FIG. 1, the push wheel 7 has a cylindrical portion 7 a that is inserted in the axial direction so as to be movable in the axial direction of the large-diameter hole 11 of the joint body 5, and through which the flexible tube 2 can be inserted. A flange 7b having an outer diameter larger than that of the large-diameter hole 11 is integrally formed on the outer periphery of the inlet-side rear end. A packing groove 18 is formed in the circumferential direction on the inner periphery of the rear end on the inlet side of the cylindrical portion 7a of the press ring 7, and a T-type waterproof packing 19 made of EPDM (ethylene / propylene / diene rubber) or the like is fitted into the packing groove 18. The gap between the inner periphery of the press ring 7 and the outer periphery of the synthetic resin layer 10 of the flexible tube 2 inserted into the press ring 7 is sealed to prevent water from entering from the outside.
A tapered taper 20a having substantially the same gradient as the second taper 16 is formed on the outer periphery of the tip portion of the cylindrical portion 7a of the press wheel 7, and a taper taper 20b is formed on the inner periphery of the tip portion of the cylindrical portion 7a. ing.

  As shown in FIG. 1, a snap ring housing and holding groove 21 is formed in the circumferential direction on the outer periphery of the cylindrical portion 7 a of the push ring 7, while the inner periphery of the large-diameter hole 11 of the joint body 5 is on the inner side from the inlet side. A first snap ring engaging groove 22 and a second snap ring engaging groove 23 are formed in the circumferential direction in this order. A taper surface 22 a that gradually narrows forward is formed on the front groove wall in the first snap ring engagement groove 22.

  A waterproof packing groove 28 is provided on the rear side of the snap ring housing and holding groove 21 of the cylindrical portion 7a of the press ring 7 or on the rear side of the first snap ring engaging groove 22 on the inner periphery of the receiving portion 3, and this waterproof packing is provided. An O-type waterproof packing 29 made of NBR, SBR rubber or the like is fitted into the groove 28 to seal the gap between the inner periphery of the large-diameter hole 11 of the receiving portion 3 and the outer periphery of the cylindrical portion 7a of the press ring 7. Prevent water from entering from the outside. A fireproof packing groove 30 is provided on the inner periphery of the medium diameter hole 12 or the small diameter hole 13 of the joint body 5, and a fireproof packing 31 made of rubber with thermally expandable graphite or the like is fitted into the fireproof packing groove 30.

  As shown in FIG. 1, the push wheel 7 is positioned and held in a semi-inserted state (initial position) located at the rear side of the retaining claw 6e of the seal rubber 6 before the flexible tube 2 is inserted as shown in FIG. As shown in FIG. 3, the holding means and the front end portion are located with a slight gap behind the retaining claw portion 6e of the sealing rubber 6 that is pushed into the small diameter hole 13 as the flexible tube 2 is inserted. A second positioning and holding means that is positioned and held at a proper pushing position.

  As shown in FIG. 1, the first positioning and holding means is configured such that the inner peripheral portion of a snap ring 27 that is freely expandable / contractible and is formed of a C-shaped retaining ring for a hole is fitted in the snap ring receiving and holding groove 21 of the push ring 7. And the outer peripheral portion of the snap ring 27 protrudes from the outer peripheral surface of the cylindrical portion 7a of the push ring 7 and is detachably engaged with the first snap ring engaging groove 22 of the joint body 5. The snap ring 27 is housed in the snap ring housing / holding groove 21 in a state where the diameter can be increased.

  By means of the first positioning and holding means, as shown in FIG. 1, the pusher wheel 7 is a retaining claw in which the tip of the pusher wheel 7 in a half-inserted state is positioned in the medium diameter hole 12 of the seal rubber 6 before the flexible tube 2 is inserted. It is positioned and held at the initial position located on the rear side of the portion 6e. That is, the push wheel 7 in the half-inserted state is reliably prevented from being pushed by the engaging action between the outer peripheral portion of the snap ring 27 and the first snap ring engaging groove 22 at the initial position. The push wheel 7 is prevented from being inadvertently pushed from the half-insertion state of the initial state by the first positioning and holding means, thereby preventing a problem that the seal rubber 6 is inadvertently pushed and deformed.

  In the second positioning and holding means, the second snap ring engaging groove 23 is arranged in front of the first snap ring engaging groove 22 on the inner periphery of the receiving portion 3, and the push ring 7 in the half-inserted state is pushed in. As it is turned, the snap ring 27 is configured to slide out of the tapered surface 22a of the first snap ring engaging groove 22 and engage with the second snap ring engaging groove 23 (see FIG. 3). The stroke length S (see FIG. 2), which is the pushing allowance of the push wheel 7, is set to be substantially the same as the distance between the first snap ring engaging groove 22 and the second snap ring engaging groove 23. Has been.

  Next, a procedure for connecting the flexible pipe 2 to the flexible pipe joint 1 will be described with reference to FIGS.

  As shown in FIG. 1, when the joint 1 is stocked / stored or transported before the flexible pipe 2 is connected, the first snap ring 27 is engaged with the first snap ring engaging groove 22 by the engaging action of the outer periphery of the snap ring 27. With this positioning and holding means, it is possible to prevent the occurrence of a troublesome situation in which the half-inserted push wheel 7 is inadvertently pushed and deforms the seal rubber 6.

  When connecting the flexible tube 2, first, the tip of the metal corrugate tube 2 a of the flexible tube 2 where the synthetic resin layer 10 is peeled off and about six peaks 8 are exposed from the inlet side of the presser wheel 7 to the joint body. 5 is inserted in the order of the retaining claw portion 6e of the seal rubber 6 in the receiving portion 3, the rear barrel portion 6d, the seal action portion 6c, and the front barrel portion 6a, and the tip of the metal corrugate tube 2a is inserted into the seal rubber 6 It is made to contact | abut to the pipe end receiving part 6b. At that time, since the sealing action portion 6c of the seal rubber 6 is formed so as to protrude outward, the distal end portion of the flexible pipe 2 is not disturbed when the flexible pipe 2 is inserted. It can be smoothly inserted into the seal rubber 6.

  Subsequently, when the flexible tube 2 is inserted to a predetermined depth as shown in FIG. 2, the seal rubber 6 is pushed into the receiving portion in the inner direction along with the flexible tube 2, and the seal action portion 6 c of the seal rubber 6 is first tapered along with this pushing. 15 is pressed by the first taper 15 by sliding in contact with the narrowed side of 15 and deformed inwardly, and as soon as it passes through the first tapered surface 15 and moves into the small-diameter hole 13, the valley of the flexible tube 2. When the slope 9a and the valley bottom 9b of the portion 9 are in close contact with each other or at least the slope 9a in a compressed state, the retaining claw 6e of the seal rubber 6 is slidably brought into contact with the narrowed side of the second taper 16 at the same time. The taper 16 moves to the medium diameter hole 12 while being pressed in the diameter reducing direction. As a result, the space between the outer peripheral surface of the distal end portion of the flexible tube 2 and the inner peripheral surface of the small-diameter hole 13 of the joint body 5 is reliably sealed and sealed by the seal rubber 6, and the fluid flowing in the flexible tube 2 flows. Thus, it is possible to prevent leakage from passing between the outer periphery of the distal end portion of the flexible tube 2 and the inner periphery of the small diameter hole 13 of the joint body 5. A sealing function can also be expected between the tip of the flexible tube 2 and the tube end receiving portion 6b of the seal rubber 6.

When the flexible tube 2 is inserted to a predetermined depth as shown in FIG. 2, the inner diameter portion of the tube end receiving portion 6 b of the seal rubber 6 and the inner surface of the distal end portion of the flexible tube 2 are the check claws 17 b of the distal end latching member 17. And the inner periphery of the small-diameter hole 13 are engaged with the check claw 17b after passing through the elastic claw deformation of the check claw 17b. When this pipe end receiving portion 6b passes through the check claw 17b, the installer feels responsive and can feel that the flexible pipe 2 has been inserted to a predetermined depth.
Moreover, while the front-end | tip part of the flexible pipe | tube 2 engages with the non-return claw 17b of the front-end | tip latching member 17, the flexible claw part 6e enters into the trough part 9, and it suppresses that the flexible pipe | tube 2 shakes. can do.

  After the insertion of the flexible tube 2 is completed, the push ring 7 is completely pushed in by the pushing allowance as shown in FIG. Along with this pushing, the snap ring 27 is in sliding contact with the tapered surface 22a of the first snap ring engagement groove 22 of the joint body 5 in a state where the inner peripheral portion is fitted and accommodated in the snap ring accommodation holding groove 21. The diameter is elastically reduced. When the press ring 7 is completely pushed in, the outer peripheral portion of the reduced diameter snap ring 27 reaches the second snap ring engaging groove 23, and the snap ring 27 is expanded in diameter by an elastic restoring action, and the outer peripheral portion. The second positioning and holding means for engaging with the second snap ring engaging groove 23 acts. As a result, the pusher wheel 7 is held at a complete pushing position where the tip of the pusher wheel 7 is located behind the retaining claw 6e of the seal rubber 6, so that the seal rubber 6 moves back toward the inlet side of the receiving port 3. Can be prevented. Therefore, the sealing state by the seal rubber 6 can be ensured.

  Further, as the push ring 7 is completely pushed, the taper 20 b at the tip end of the push ring 7 comes close to and opposes the taper 25 of the retaining claw 6 e of the seal rubber 6. Therefore, even if an external force is applied in the direction in which the flexible tube 2 is pulled out at this time, the taper 25 of the retaining claw portion 6e that accompanies the flexible tube 2 comes into contact with the constricted side of the taper 20b of the push ring 7, so The tube 2 is reliably prevented from coming out.

  In the joint for flexible pipe as described above, the present invention selects gas but allows solids and liquids to pass through several places in the circumferential direction of the O-type waterproof packing 29 as shown in FIGS. It is characterized in that the gas permeable inspection is made possible by embedding the permeable member 26 integrally.

Ventilation holes 29a are provided at several locations in the circumferential direction of the O-type waterproof packing 29 so as to penetrate in the packing axial direction (front-rear direction), and a pin-shaped selectively permeable member 26 is press-fitted into the ventilation holes 29a. . In addition, the selectively permeable member 26 can be integrally formed when the O-type waterproof packing 29 is formed.
The permselective member 26 has, for example, a continuous pore formed from a sheet material including a continuous porous film formed from a tetrafluoroethylene resin powder, or a thermoplastic resin powder such as polyethylene, polypropylene, polymethyl acrylate, or the like. It is a porous body.

  As shown in FIG. 6, the O-type waterproof packing 29 has a front and rear end walls 29 a and 29 c in the packing groove 28, and the front and rear end surfaces 29 b and 29 c of the O-type waterproof packing 29 are formed in the waterproof packing groove 28 of the push ring 7 or the receiving portion 3. 28b, so as to form gaps 32a and 32b, respectively. As a result, the front and rear end surfaces 26a and 26b of the selectively permeable member 26 exposed at the front and rear end surfaces 29b and 29c of the O-type waterproof packing 29 face the gaps 32a and 32b. The gaps 32 a and 32 b communicate with a gap 33 between the outer periphery of the cylindrical portion 7 a of the push wheel 7 and the inner periphery of the receiving portion 3.

  By configuring in this way, at the time of gas leakage inspection, the gas leaked from the nailing portion or the like of the metal corrugate pipe 2a passes through the gap between the metal corrugate pipe 2a and the synthetic resin layer 10 and the joint body 5 The gap 33 between the inner periphery of the receiving portion 3 and the outer periphery of the pusher wheel 7 on the front side of the O-type waterproof packing 29 and between the front end surface 29b of the O-type waterproof packing 29 and the inside of the packing groove 28 The permselective member 26 is transmitted through the gap 32a, and the gap 32b between the rear end surface 29c of the O-type waterproof packing 29 and the packing groove 28, and the inner periphery of the receiving portion 3 and the O-type waterproof of the press ring 7 are provided. It leaks to the outside through the gap 33 between the outer periphery behind the packing 29. As a result, it is reliably detected that the sealing pressure is reduced and there is a leak.

  In this manner, the O-type waterproof packing 29 that seals the gap between the outer periphery of the push wheel 7 and the inner periphery of the receiving portion 3 has a function that enables leak detection in addition to the original waterproof function.

  In the above embodiment, the joint portion for the male threaded flexible pipe in which the receiving port 3 is formed at one end of the joint body 5 and the male thread for connection 4 is formed at the outer periphery of the other end is described, but the present invention is not limited thereto, and other structures, For example, the present invention can be applied to symmetrical socket-type flexible pipe joints having receiving portions at both ends, elbow-type flexible pipe joints, and the like.

It is a half notched cross-sectional view showing the joint for flexible pipe showing an embodiment of the present invention in a state before insertion of the flexible pipe. It is a half notched cross-sectional view of the joint for flexible pipes shown in the state during insertion of the flexible pipes. It is a half notched cross-sectional view of the joint for flexible pipes shown in a state after completion of insertion of the flexible pipes. (A) is a half cutaway cross-sectional view of the seal rubber, (b) is a rear view of the seal rubber, and (c) is a side view of the seal rubber. (A) is a front view of O type waterproof packing, (b) is the sectional view on the AA line in Fig.5 (a). It is an expanded sectional view of the O-type waterproof packing part in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Joint for flexible pipes 2 Flexible pipe 2a Metal corrugate pipe 3 Receptacle part 5 Joint body 6 Seal rubber 7 Push ring 10 Synthetic resin layer 29 O type waterproof packing 29a Vent hole 29b Front end surface of O type waterproof packing 29c After O type waterproof packing End face 26 Selective permeability member 26a Front end face of selective permeability member 26b Rear end face of selective permeability member 32a, 32b Gap 33 Gap

Claims (3)

A joint body having a receiving portion, a push ring inserted into the receiving portion, a flexible pipe inserted into the receiving portion from the push ring and having a synthetic resin layer coated on the outer periphery of a metal corrugate pipe, and Sealed in the gap between the outer periphery in the vicinity of the tip portion, which is accommodated in the receiving portion and exposed without being covered with the synthetic resin layer of the flexible pipe inserted into the receiving portion, and the inner periphery of the receiving portion. A seal rubber and an O-type waterproof packing that is fitted in a waterproof packing groove provided on the inner periphery of the receiving part or on the outer periphery of the press ring, and seals a gap between the inner periphery of the receiving part and the outer periphery of the press ring; In a flexible pipe joint comprising:
A selective permeable member that transmits gas but does not transmit solids or liquids is embedded in several portions in the circumferential direction of the O-type waterproof packing in the packing axial direction, and exposed to both front and rear end faces of the O-type waterproof packing. The front and rear end faces of the selectively permeable member are between the inside of the packing groove and the front and rear end faces of the O-type waterproof packing so as to communicate with a gap between the inner periphery of the receiving port and the outer periphery of the push ring. A flexible pipe joint characterized by facing a gap formed in   The permselective member is a sheet material including a continuous porous film formed from a tetrafluoroethylene resin powder, or a porous material having continuous pores formed from a thermoplastic resin powder such as polyethylene, polypropylene, and polymethyl acrylate. The joint for flexible pipes according to claim 1 which is a body.   The vent hole is provided in several places in the circumferential direction of the O-type waterproof packing so as to penetrate in the packing axial direction, and a pin-shaped selectively permeable member is press-fitted into the vent hole. For flexible pipes.

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