JP2011007237A - Flexible pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible pipe joint which can be disassembled by easily extracting a snap ring.SOLUTION: This flexible pipe joint 10 includes a joint body 20 having an insertion opening, a pressing ring 22, a slipping-out preventive member 64, and the shape memory alloy snap ring 26. The snap ring 26 prevents the pressing ring 22 from slipping out of the joint body 20. The inner peripheral surface of the joint body 20 is formed with a snap ring temporarily fastening groove and a pressing ring slipping-out preventive groove. A pressing ring retaining groove 84 is formed in the portion of the press ring 22, opposed to the snap ring temporarily fastening groove and pressing ring slipping-out preventive groove in the joint body 20. The inner peripheral portion of the snap ring 26 is fitted to the pressing ring retaining groove 84. The snap ring 26 is applied with shape-memory treatment so that an outside diameter is contracted until the snap ring slips out of the pressing ring slipping-out preventive groove according to the fact that the temperature of the snap ring exceeds phase transition temperature of shape memory alloy.

Description

  The present invention relates to a flexible pipe joint, and more particularly to a flexible pipe joint that can be easily disassembled.

  Patent document 1 discloses the joint for flexible pipes. This flexible pipe joint includes a joint body, a seal rubber, and a press ring. The joint body has a receiving portion. Inserted into this receptacle is the tip of a flexible tube (the outer periphery of the flexible tube has crests and troughs extending in the circumferential direction alternately arranged in parallel in the tube axis direction) Is done. The seal rubber is accommodated in the receiving part, and seals between the inner periphery of the receiving part and the outer periphery near the tip of the flexible tube inserted into the receiving part. The pusher wheel is inserted into the receiving part. The pusher wheel is inserted in a semi-insertion state that leaves a pushing allowance in the receiving part. When the pusher wheel is completely pushed by the pushing amount, the seal rubber is prevented from returning and moving toward the inlet side of the receiving part at the tip part. A large-diameter hole, a medium-diameter hole, and a small-diameter hole are formed in the receiving portion in order from the inlet side toward the inner back side. A cylindrical front barrel having an inner diameter substantially the same as the outer diameter of the ridge of the flexible tube, a tube end receiving portion projecting inwardly at the front end of the front barrel, and a rear end of the front barrel An annular sealing action part projecting outward from the part, a rear trunk part having an inner diameter larger than the inner diameter of the front trunk part connected to the rear from the sealing action part, and a rear side part connected to the rear end part of the rear trunk part It is integrally formed in a shape having a retaining protrusion having an inner diameter smaller than the inner diameter of the body portion and larger than the outer diameter of the mountain portion and larger than the outer diameter of the rear body portion. A first taper is formed between the small diameter hole and the medium diameter hole so as to be narrowed toward the small diameter hole. A second taper is formed between the medium diameter hole and the large diameter hole so as to be narrowed toward the medium diameter hole. In the free state, the tube end receiving portion and the front body portion of the seal rubber are located in the small diameter hole, the sealing action portion is located in the medium diameter hole, and the retaining projection is located in the large diameter hole. Contained. As the distal end of the flexible tube is inserted into the receiving part through the press ring in the half-inserted state, the distal end of the flexible pipe is inserted into the seal rubber and comes into contact with the tube end receiving part, and the seal rubber is inserted into the receiving part. Push inward. With this pushing, the sealing action part is slidably brought into contact with the narrowed side of the first taper, so that the diameter of the sealing action part is reduced, and the sealing action part comes into close contact with at least the slope of the valley of the flexible tube. Further, the retaining protrusions reduce the diameter by sliding the outer diameter portion thereof toward the constriction side of the second taper, and the inner diameter portion is fitted into the valley portion of the flexible tube.

  According to this flexible pipe joint, the flexible pipe can be connected in a seal-like manner by a one-touch operation of inserting the flexible pipe and pushing the push ring.

JP 2009-127757 A

  However, the joint for flexible pipes disclosed in Patent Document 1 has a problem that it is difficult to disassemble the joint for flexible pipes once the flexible pipes are connected and the press ring is pushed into the joint body. That is, the joint body of the joint for flexible pipe disclosed in Patent Document 1 is integrated. When the snap ring is inserted into this joint body and the pusher wheel is pushed into the back, the outer periphery of the snap ring fits into the groove provided on the inner peripheral surface of the joint body, and the inner periphery of the snap ring is brought into contact with the outer peripheral surface of the pusher wheel. Fits into the groove provided. This prevents the pusher wheel from coming out of the joint body. In order to disassemble the joint for flexible pipe disclosed in Patent Document 1, it is necessary to extract the snap ring from at least one of the groove provided on the inner peripheral surface of the joint main body and the groove provided on the outer peripheral surface of the press ring. If the snap ring can be easily extracted from at least one of the grooves, there is a high risk that the flexible pipe will unexpectedly come out of the flexible pipe joint. If the risk of the flexible pipe unexpectedly falling out of the flexible pipe joint is reduced, it becomes difficult to remove the snap ring from at least one of the grooves.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a joint for a flexible pipe in which a snap ring can be easily extracted and disassembled.

  The joint for flexible pipes of this invention is demonstrated with reference to drawings. Note that the use of the reference numerals in the figure in this column is intended to assist understanding of the contents of the invention, and is not intended to limit the contents to the illustrated range.

  In order to achieve the above object, according to an aspect of the present invention, the flexible pipe joint 10 includes a joint body 20 having an insertion port 30, a retaining member 64, and a push ring 22. The retaining member 64 is accommodated in the joint body 20. The pusher wheel 22 is inserted into the joint body 20 through the insertion port 30. The flexible tube 300 passes through the push wheel 22 and is inserted into the joint body 20 from the insertion port 30. The retaining member 64 engages with the outer peripheral surface of the flexible tube 300. The retaining ring 64 in a state where the pusher wheel 22 is engaged with the outer peripheral surface of the flexible tube 300 is prevented from coming out of the joint body 20. The flexible pipe joint 10 further includes a snap ring 26 made of a shape memory alloy. The snap ring 26 prevents the pusher wheel 22 from coming out of the joint body 20. A snap ring temporary retaining groove 92 and a push ring retaining groove 94 are provided on the inner peripheral surface of the joint body 20. The press ring retaining groove 94 is arranged on the back side as viewed from the insertion port 30 with respect to the snap ring temporary retaining groove 92. A push ring holding groove 84 is provided in a portion of the push ring 22 that faces the snap ring temporary retaining groove 92 and the push ring retaining groove 94 in the joint body 20. The inner peripheral portion of the snap ring 26 is fitted in the push ring holding groove 84. The outer peripheral portion of the snap ring 26 is fitted into the snap ring temporary retaining groove 92 in advance, and the snap ring 22 comes out of the snap ring temporary retaining groove 92 and fits into the push wheel retaining groove 94 as the push ring 22 is pushed into the joint body 20. The snap ring 26 is subjected to shape memory processing so that the outer diameter is reduced until the snap ring 26 comes out of the push ring retaining groove 94 when the temperature exceeds the phase transition temperature of the shape memory alloy.

  When the temperature of the snap ring 26 exceeds the phase transition temperature of the shape memory alloy, the outer diameter of the snap ring 26 is reduced until the snap ring 26 comes out of the push ring retaining groove 94. As a result, the snap ring 26 comes out of the push ring retaining groove 94, so that the push ring 22 can come out of the joint body 20. As the push ring 22 can come out of the joint body 20, both the retaining member 64 and the flexible pipe 300 can come out of the joint body 20. As a result, the flexible pipe joint 10 that can be easily disassembled can be provided.

  ADVANTAGE OF THE INVENTION According to this invention, the coupling for flexible pipes which can extract a snap ring easily and can disassemble can be provided.

It is sectional drawing which shows the coupling for flexible pipes concerning the Example of this invention. It is sectional drawing which shows the coupling main body concerning the Example of this invention. It is a top view of the snap ring concerning the Example of this invention. It is A arrow directional view of the coupling for flexible pipes concerning the Example of this invention. It is an enlarged view of the metal nail | claw concerning the Example of this invention. It is a perspective view of the push ring concerning the Example of this invention. It is a figure which shows the mechanism in which the coupling for flexible pipes concerning the Example of this invention fixes a flexible pipe. It is a figure which shows the condition where the joint for flexible pipes concerning the Example of this invention is decomposed | disassembled.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  As shown in FIG. 1, the flexible pipe joint 10 according to the present embodiment includes a metal joint body 20 and a push ring 22. A malfunction prevention collar 110 is fitted between the joint body 20 and the push ring 22. Since the structure of the malfunction prevention collar 110 is well known, detailed description thereof will not be repeated here.

  The structure of the joint body 20 will be described with reference to FIG. An insertion port 30 is formed at one end of the joint body 20. A male screw is formed at the other end (not shown) of the joint body 20. The insertion port 30 is a port for receiving the distal end portion of the flexible tube 300 (in this embodiment, the material of the flexible tube 300 is different from that of the joint body 20). The inside of the joint body 20 communicates with the outside of the joint body 20 through the insertion port 30. In the description of the present invention, “communication” means that two spaces are made continuous through a passage. The “passage” here includes not only a tubular shape but also a simple hole. The flexible tube 300 passes through the push ring 22 and is inserted into the joint body 20 from the insertion port 30.

  Inside the joint body 20, a first housing portion 42, a second housing portion 44, a sealing material diameter-reducing guide portion 46, and a sealing material housing portion 48 are provided. Among these, the first accommodating portion 42 is located closest to the insertion port 30. Among these, the seal material container 48 is located on the innermost side. The first accommodating portion 42 is formed at the back of the insertion port 30 and communicates with the insertion port 30. The second storage portion 44 is formed in the back of the first storage portion 42 and communicates with the first storage portion 42. The seal material diameter-reducing guide portion 46 is formed at the back of the second housing portion 44. The seal material diameter-reducing guide portion 46 is narrowed away from the second housing portion 44. The seal material accommodating portion 48 is formed at the back of the seal material diameter reducing guide portion 46. The sealing material accommodating portion 48 accommodates the distal end portion of the flexible tube 300 and the sealing material 24 on the outer periphery of the distal end portion. The description about the sealing material 24 is mentioned later.

  The first accommodating portion 42 includes a grooved portion 54 and a retaining diameter reducing guide surface 56. The grooved portion 54 communicates with the insertion port 30. The retaining diameter reducing guide surface 56 is provided at a boundary portion with the second housing portion 44. The removal-reducing diameter guide surface 56 is narrowed away from the insertion port 30.

  The grooved portion 54 is provided with a snap ring temporary retaining groove 92 and a push ring retaining groove 94. These extend in a direction perpendicular to the central axis of the joint body 20. As will be described later, a snap ring 26 is fitted into these. The push ring retaining groove 94 is provided at a position farther from the insertion port 30 than the snap ring temporary retaining groove 92 (inner side as viewed from the insertion port 30). A groove taper surface 92 a is formed on the inner inner groove wall in the snap ring temporary fixing groove 92. The groove taper surface 92a is narrowed in the direction of the second accommodating portion 44 (inward and backward direction when viewed from the insertion port 30).

  A fireproof packing groove 96 is provided on the inner periphery of the second housing portion 44 so as to surround the outer periphery of the sealing material 24. A fireproof packing 104 is fitted in the fireproof packing groove 96. In this embodiment, the fireproof packing 104 is made of rubber with thermally expandable graphite.

  A stopper portion 50 is provided at the inner back end of the sealing material accommodating portion 48. The stopper portion 50 protrudes in the direction of the central axis of the joint body 20 as compared with the sealing material housing portion 48.

  With reference to FIG. 1 again, the arrangement and role of the pusher wheel 22, the sealing material 24, and the snap ring 26 will be described. The pusher wheel 22 is connected to the joint body 20 in a temporarily inserted state that leaves a pushing allowance. The sealing material 24 is accommodated in the joint body 20 through the insertion port 30 of the joint body 20. The seal member 24 is disposed on the inner back side (the male screw side (not shown)) of the joint body 20 with respect to the pusher wheel 22. The snap ring 26 is accommodated in the joint body 20. The snap ring 26 is an engaging member that can expand and contract in the radial direction.

  The snap ring 26 will be described with reference to FIGS. 1 and 3. The snap ring 26 according to this embodiment is a ring formed of a wire. However, part of the ring is broken. That is, as shown in FIG. 3, the outer shape of the snap ring 26 is C-shaped. The material of the snap ring 26 is a shape memory alloy. The type of the shape memory alloy used as the material of the snap ring 26 is not particularly limited, but those that exhibit a two-way shape memory effect are preferable. By using such a shape memory alloy as a raw material, the outer diameter of the push ring 22 is prevented from coming off at room temperature and the snap ring 26 is heated (that is, the outside of the joint body 20 is exposed to fire). This is because the function of decreasing can be sufficiently exhibited.

  The structure of the sealing material 24 will be described with reference to FIGS. 1 and 4. The sealing material 24 according to the present embodiment has an engaging portion 61 and a sealing action portion 62. A tube insertion hole 63 is formed in the center of the sealing material 24. The flexible tube 300 is inserted into the tube insertion hole 63. The engaging portion 61 is pushed by the flexible tube 300 inserted into the tube insertion hole 63, whereby the sealing material 24 is inserted into the joint body 20 at a position where the fitting main body 20 is completely inserted (in the present embodiment, a predetermined position in the sealing material accommodating portion 48). It is a part to move to. The seal action part 62 projects outward from the rear end part of the engagement part 61. When the sealing action part 62 engages with the valley 312 of the flexible tube 300, the inner peripheral surface of the joint body 20 and the outer peripheral surface of the flexible tube 300 are sealed.

  The engaging part 61 has a cylindrical part 61a and a pipe end receiving part 61b. The inner diameter of the cylindrical portion 61 a is substantially the same as the outer diameter of the peak portion 310 of the flexible tube 300. The tube end receiving portion 61b projects inwardly from the front end portion of the tubular portion 61a. When the flexible pipe 300 is inserted into the joint body 20, the pipe end receiving portion 61 b hits the tip of the flexible pipe 300.

  A plurality of retaining members 64 are provided on the rear side of the sealing material 24, that is, on the side closer to the insertion port 30 than the engaging portion 61. These retaining members 64 are arranged so as to be arranged in the circumferential direction. The retaining members 64 are separated from each other by a predetermined interval. When the sealing material 24 is accommodated in the joint body 20, the diameter of the space surrounded by the retaining member 64 is larger than the outer diameter of the peak portion 310 of the flexible pipe 300. The retaining member 64 is located at a position before the seal material 24 has not reached the insertion completion position of the joint body 20 (in this embodiment, the position shown in FIG. 1), and the pusher wheel 22. When the push ring 22 is pushed, it stands in front of the push ring 22 to prevent the snap ring 26 from being fitted into the push ring retaining groove 94.

  In the present embodiment, the engaging portion 61 and the retaining member 64 are integrated.

  In the case of the present embodiment, the cylindrical portion 61a, the pipe end receiving portion 61b, the sealing action portion 62, and a part of the retaining member 64 are made of rubber. Examples of these materials include NBR (Acrylonitrile-Butadiene Rubber), SBR (Styrene-butadiene rubber), and EPDM (ethylene propylene rubber). These are all rubber. Furthermore, the material of these surface portions may be formed of the same material or different materials. Of course, it may be formed of the same material as the coating layer 314 of the flexible tube 300, or may be formed of a different material.

  As shown in FIG. 1, a reinforcing cored bar 61f such as a brass washer is embedded in the pipe end receiving part 61b. A metal claw 70 (brass is an example of a metal claw material) is provided at the tip of the retaining member 64. Of the metal claw 70, a portion that contacts the outer peripheral surface of the flexible tube 300, a portion that contacts the inner surface of the joint body 20, and a portion that contacts the push ring 22 (more specifically, in the case of this embodiment, the metal claw 70 All of the outer peripheral surfaces except for the side surface that does not contact the flexible tube 300 and the joint body 20 are covered with rubber integrated with the engaging portion 61.

  The metal claw 70 stands in front of the pusher wheel 22 when pushed by the pusher wheel 22. Further, the metal claw 70 engages with the valley 312 of the flexible tube 300.

  A specific structure near the metal claw 70 will be described with reference to FIG. The metal claw 70 includes a restraining portion 70a, a retaining portion 70b, an inner peripheral surface facing portion 70c, and a push wheel facing portion 70d. The restraining portion 70a is pressed against the retaining diameter reducing guide surface 56 by a tip portion 82a, which will be described later, of the pusher wheel 22 (for this reason, the retaining diameter reducing guiding surface 56 receives the metal claw 70). The retaining portion 70 b moves from the first accommodating portion 42 into the second accommodating portion 44 as the engaging portion 61 is pushed into the back of the sealing material accommodating portion 48. The retaining portion 70 b fits on the outer periphery of the flexible tube 300 as it moves from the first housing portion 42 into the second housing portion 44. The inner peripheral surface facing portion 70 c is a portion facing the inner peripheral surface of the joint body 20. The push wheel facing portion 70 d is a portion that contacts the push wheel 22 when a pulling force is applied to the flexible tube 300. Since the portion made of rubber in the retaining portion 64 extends to the restraining portion 70a, when the sealing material 24 is moved in the withdrawal direction by pulling out the flexible tube 300, the retaining portion 64 is connected to the flexible tube 300. The state before the insertion can be restored and separated from the valley 312 to release the engagement. Further, since the portion of the retaining portion 64 made of rubber extends to the retaining portion 70b, the elastic force for returning the retaining portion 64 to the state before insertion of the flexible tube 300 is high.

  The sealing material 24 is arranged as shown in FIG. 1 before the flexible tube 300 is inserted (initial state). Thereby, in the initial state, the pipe end receiving portion 61b and the cylindrical portion 61a are located in the sealing material accommodating portion 48, the sealing action portion 62 is located in the second accommodating portion 44, and the retaining member 64 The sealing material 24 is arranged so that the tip portion is located at the obstructing position in the first accommodating portion 42.

  The structure of the push wheel 22 will be described with reference to FIGS. 1 and 6. The pusher wheel 22 is inserted into the joint body 20. In the insertion port 30, the push wheel 22 is movable in the axial direction. The flexible tube 300 can be inserted through the push ring 22.

  A tip end portion 82 a is provided at a portion of the pusher wheel 22 that faces the retaining member 64. As will be apparent from the following description, when the retaining ring 64 is disposed at the obstructing position, the tip end portion 82a is detached from the inner peripheral surface of the first housing portion 42 when the pusher wheel 22 is pushed into the joint body 20. The stop member 64 is pressed. More specifically, in the case of the present embodiment, the retaining member 64 that is pressed is received by the retaining diameter reducing guide surface 56 of the first accommodating portion 42.

  The tip portion 82a has an inclined surface 106a and a tip surface 106b. The shape of the inclined surface 106a is a tapered shape. As a result, the inclined surface 106 a is narrowed as it approaches the tip of the push wheel 22. In this embodiment, the slope of the inclined surface 106 a is substantially the same as that of the retaining diameter reducing guide surface 56 provided in the joint body 20. The front end surface 106 b of this embodiment is a flat surface that is disposed at the front end of the press wheel 22. Of course, the tip surface 106b may be a curved surface or other surfaces. Incidentally, the inner diameter at the end on the center side of the push wheel 22 in the tip surface 106 b is equal to or larger than the inner diameter of the second housing portion 44.

  A reaction force portion 82 b is provided on the inner periphery of the tip portion of the pusher wheel 22 that faces the retaining member 64. The reaction force portion 82 b has a shape that expands toward the back of the insertion port 30.

  In FIG. 6, an outer peripheral surface facing portion 82 c is provided in a portion corresponding to the back of the reaction force portion 82 b. When the flexible tube 300 passes through the pusher wheel 22 and the coating layer 314 of the flexible tube 300 hits the abutting part of the pusher wheel 22, the outer peripheral surface facing part 82 c is formed on the outer peripheral surface (the peak part 310 and the valley part). 312 is a portion facing a portion exposed as a result of peeling of the coating layer 314.

  As shown in FIG. 6, a pusher wheel retaining groove 84 is provided on the surface of the pusher wheel 22 that faces the inner periphery of the joint body 20. The presser wheel holding groove 84 is formed in a direction orthogonal to the central axis of the presser wheel 22.

  A waterproof packing groove 86 is provided in a portion of the pusher wheel 22 on the inlet side of the pusher wheel retaining groove 84. The waterproof packing 102 is fitted in the waterproof packing groove 86.

  As shown in FIG. 1, a malfunction prevention collar 110 is fitted in the insertion planned portion 77. The insertion-scheduled portion 77 is that the outer periphery of the snap ring 26 of the press ring 22 is exposed from the joint main body 20 when the snap ring 26 is fitted in the snap ring temporary fixing groove 92, and the outer periphery of the snap ring 26 is the press ring retaining groove 94. It is a portion arranged in the insertion slot 30 when it is fitted.

  The pushing allowance of the push ring 22 is set to be substantially equal to the distance between the snap ring temporary retaining groove 92 and the push ring retaining groove 94.

  Next, the point which connects the flexible pipe | tube 300 to the joint 10 for flexible pipes mentioned above is demonstrated, referring FIG.

  When connecting the flexible tube 300, first, the flexible tube 300 is inserted into the insertion port 30 of the joint body 20 from the inlet side of the pusher wheel 22. Note that the coating layer 314 at the distal end portion of the flexible tube 300 is peeled in advance so that the eight crests 310 are exposed. However, how many peak portions 310 are exposed is determined according to the size of the joint body 20 and the like. How many peak portions 310 are exposed is not limited to that of the present embodiment.

  The flexible tube 300 inserted into the insertion port 30 passes through the sealing material 24 in the order of the retaining member 64, the sealing action portion 62, and the cylindrical portion 61a. Thereafter, as shown in FIG. 7A, the distal end portion of the flexible tube 300 abuts against the tube end receiving portion 61 b of the sealing material 24. At this time, since the sealing action part 62 of the sealing material 24 is formed so as to project outward, the sealing action part 62 does not become an obstacle when the flexible pipe 300 is inserted. The distal end portion of the flexible tube 300 can be smoothly inserted into the sealing material 24.

  When the flexible tube 300 is inserted until it hits the tube end receiving portion 61 b of the sealing material 24, the tubular portion 61 a of the sealing material 24 is pushed into the depth of the sealing material accommodation portion 48. Along with this pushing, the sealing action part 62 of the sealing material 24 moves to the narrow side of the sealing material diameter-reducing guide part 46. The sealing action part 62 is pressed by the sealing material diameter reducing guide part 46 and is reduced in diameter inwardly. The sealing action part 62 engages with the valley 312 of the flexible tube 300 as soon as it passes through the sealing material diameter reducing guide part 46 and is drawn into the sealing material accommodating part 48. At that time, the sealing action part 62 is in close contact with the slope of the valley 312. At the same time, the retaining member 64 moves to the narrowing side of the retaining diameter reducing guide surface 56. The retaining member 64 is pulled into the second housing portion 44 while being pushed in the diameter reducing direction by the retaining diameter reducing guide surface 56. As a result, as shown in FIG. 7B, the seal material 24 reliably seals the gap between the outer peripheral surface of the distal end portion of the flexible tube 300 and the inner peripheral surface of the seal material accommodating portion 48 of the joint body 20. The By sealing hermetically there, it is possible to prevent the fluid flowing in the flexible tube 300 from leaking from the joint body 20. Even if the flexible tube 300 is slightly deformed, the effect is hardly lowered. It should be noted that a sealing function can also be expected between the distal end portion of the flexible tube 300 and the tube end receiving portion 61 b of the sealing material 24. FIG. 7B shows a situation in which the inner diameter portion of the tube end receiving portion 61 b of the sealing material 24 and the inner surface of the distal end portion of the flexible tube 300 abut against the stopper portion 50 at the back of the sealing material accommodation portion 48.

  After the insertion of the flexible tube 300 is completed, the malfunction prevention collar 110 is removed from the pusher wheel 22. When the malfunction prevention collar 110 is removed, the pusher wheel 22 is completely pushed. Along with this pushing, the snap ring 26 slides out of the snap ring temporary fixing groove 92 along the groove tapered surface 92a in a state where the inner peripheral portion is fitted in the push ring holding groove 84. Since it moves along the groove taper surface 92a, the snap ring 26 is elastically deformed to reduce its diameter. When the push ring 22 is completely pushed in, the outer peripheral portion of the snap ring 26 is fitted into the push ring retaining groove 94. When the outer peripheral portion of the snap ring 26 is fitted in the push ring retaining groove 94, the diameter of the snap ring 26 that has been reduced in diameter is increased. Thereby, the position of the push wheel 22 can be fixed. FIG. 7C shows a state where the pusher wheel 22 is completely pushed. The front end portion of the push wheel 22 is held at a complete pushing position located on the rear side of the retaining member 64. At this time, as clearly shown in FIG. 7C, the sealing state by the sealing material 24 is ensured.

  Further, as the push wheel 22 is completely pushed, the reaction force portion 82b at the tip end of the push wheel 22 comes close to and faces the retaining member 64. Thereafter, when a pulling force is applied to the flexible pipe 300 in the pulling direction from the joint body 20, the retaining member 64 slightly moves in the direction of the insertion port 30 and contacts the reaction force portion 82 b. The retaining member 64 receives a reaction force from the reaction force portion 82b when it comes into contact with the reaction force portion 82b. When the retaining member 64 receives a reaction force from the reaction force portion 82 b, the retaining portion 70 b moves toward the bottom of the valley portion 312 of the flexible tube 300. The retaining member 64 receives a reaction force from the reaction force portion 82b, and the retaining portion 70b transmits the reaction force to the flexible tube 300, so that the flexible tube 300 is prevented from coming out.

  Next, a procedure for disassembling the flexible pipe joint 10 to which the flexible pipe 300 is connected and removing the flexible pipe 300 will be described with reference to FIG.

  First, the outer periphery of the flexible pipe joint 10 to which the flexible pipe 300 is connected is heated by a heat source (not shown) (for example, a burner flame). Thereby, heat is transmitted to the snap ring 26 through the joint body 20. If the temperature of the snap ring 26 exceeds the phase transition temperature as a result of heat transfer, the outer diameter of the snap ring 26 shrinks. The outer diameter of the snap ring 26 is reduced. FIG. 8A shows a situation where the snap ring 26 is contracted.

  After the snap ring 26 contracts, the operator grasps the flexible pipe 300 by hand and pulls it out of the flexible pipe joint 10. At this time, the sealing material 24 is engaged with the outer periphery of the flexible tube 300. A retaining member 64 provided on the sealing material 24 faces the pusher wheel 22. Therefore, when the flexible pipe 300 is pulled out from the flexible pipe joint 10, the push ring 22 is also pulled out from the flexible pipe joint 10. Since the sealing material 24 does not engage with the flexible pipe 300 inside the joint body 20, it remains in the flexible pipe joint 10. FIG. 8B shows a state where the pusher wheel 22 is pulled out together with the flexible tube 300.

  When the pusher wheel 22 is pulled out together with the flexible tube 300, the operator removes the pusher wheel 22 from the flexible tube 300. Further, the operator pulls out the sealing material 24 and the retaining member 64 from the joint body 20. Thereby, the disassembly of the flexible pipe joint 10 is completed.

  As described above, the flexible pipe joint 10 according to the present embodiment can be disassembled by heating after connecting the flexible pipe 300.

  The embodiments disclosed herein are illustrative in all respects. The scope of the present invention is not limited based on the above-described embodiments, and it is needless to say that various design changes may be made without departing from the spirit of the present invention.

  For example, the present invention is not limited to the flexible pipe joint in which the insertion port 30 is formed at one end of the joint body 20 and the male screw is formed at the other end of the joint body 20. The present invention is applicable to other structures such as various types of flexible pipe joints that can be used as headers, symmetrical socket-type flexible pipe joints having receiving portions at both ends, elbow-type flexible pipe joints, and the like. Of course, it is applicable.

DESCRIPTION OF SYMBOLS 10 Joint for flexible pipes 20 Joint main body 22 Push ring 24 Sealing material 26 Snap ring 30 Insertion port 42 1st accommodating part 44 2nd accommodating part 46 Sealing material diameter reducing guide part 48 Sealing material accommodating part 50 Stopper part 54 Grooved part 56 Diameter guide surface 61 Engagement part 61a Tubular part 61b Pipe end receiving part 61f Reinforcing metal core 62 Sealing action part 63 Pipe insertion hole 64 Retaining member 70 Metal claw 70a Restraining part 70b Inner peripheral surface facing part 70d Portion 77 planned insertion portion 82a tip portion 82b reaction force portion 82c outer peripheral surface facing portion 84 push ring holding groove 86 waterproof packing groove 88 abutting portion 92 snap ring temporary fixing groove 92a groove tapered surface 94 push ring retaining groove 96 fireproof packing groove 102 waterproof Packing 104 Fireproof packing 106a Inclined surface 106b Tip surface 110 Malfunction prevention collar 300 Kishiburu tube 310 crests 312 troughs 314 coating layer

Claims (1)

A joint body having an insertion port;
A retaining member housed in the joint body,
A push ring inserted into the joint body through the insertion port,
A flexible tube passes through the push ring and is inserted into the joint body from the insertion port;
The retaining member engages with the outer peripheral surface of the flexible tube;
The push ring is a joint for flexible pipes that stops the slip-off preventing member in a state of being engaged with the outer peripheral surface of the flexible pipe from coming out of the joint body,
The flexible pipe joint further includes a snap ring made of a shape memory alloy that prevents the push ring from coming out of the joint body,
The inner peripheral surface of the joint body is provided with a snap ring temporary retaining groove and a retaining ring retaining groove,
The push ring retaining groove is disposed on the back side as viewed from the insertion port with respect to the snap ring temporary retaining groove,
A push ring holding groove is provided in a portion of the push ring facing the snap ring temporary retaining groove and the push ring retaining groove in the joint body,
The inner peripheral part of the snap ring is fitted in the push ring holding groove,
An outer peripheral portion of the snap ring is fitted in the snap ring temporary retaining groove in advance, and the snap ring is pulled out from the snap ring temporary retaining groove as the push ring is pushed into the joint body, and is fitted in the push ring retaining groove.
The snap ring is subjected to shape memory processing so that the outer diameter is reduced until the snap ring comes out of the retaining ring for retaining the push ring in response to the temperature exceeding the phase transition temperature of the shape memory alloy. , Flexible pipe fittings.

Images