JP4417786B2 - Pipe fitting - Google Patents

Description

  The present invention relates to a pipe joint. In particular, it relates to a universal joint, i.e. a pipe joint having a flexible connection with a partly spherical joining surface, which has an angular movement or a mechanical connection allowing adjustment of the axis of the part in any direction.

  As a conduit having a closed cross section for transporting a fluid, for example, there is a water pipe arranged in a building or various facilities. Such a water distribution pipe connects the pipe end of one water distribution pipe and the pipe end of the other water distribution pipe so that the fluid can be transported and the angle formed by the connecting portion can be freely set to facilitate the piping work. A flexible pipe joint is used.

  In such piping work, an expansion pipe joint that freely adjusts the length of the water pipe may be used. Furthermore, an expansion / contraction flexible pipe joint having both the function of a flexible pipe joint and the function of an expansion / contraction pipe joint may be used for piping work.

  As such a pipe joint, sludge accumulation and flow rate are ensured while ensuring the desired bending performance by relative sliding between the partial spherical outer peripheral surface of the first tubular body and the partial spherical inner peripheral surface of the second tubular body. A flexible pipe joint that effectively suppresses loss has been invented (see, for example, Patent Document 1).

  The flexible pipe joint according to Patent Document 1 has a partial spherical inner peripheral surface that is slidable along a partial spherical outer peripheral surface of the first tubular body having a partial spherical outer peripheral surface protruding radially outward. A second tubular body having a length that covers a hollow portion that is formed to open radially inward at a fitting connection portion of both tubular bodies, and both pipes A sleeve made of a synthetic resin that elastically deforms following the bending of the body and substantially maintains the cylindrical shape is inserted and mounted in a contact state over the inner peripheral surfaces of both tubes.

  In addition, as another pipe joint, the angle formed by the central axes at both ends can be easily adjusted, and the direction of the central axis of each tubular member can be stably connected when connecting a hose or a socket. Pipe joints have been invented (see, for example, Patent Document 2).

  In the flexible pipe joint according to Patent Document 2, the angle formed between the central axis of the first tubular member and the central axis of the second tubular member via the intermediate tubular member is freely set between the first tubular member and the second tubular member. At the same time, at least one of the first tubular member and the second tubular member is rotatable with respect to the central axis of the intermediate tubular member, and a fluid is supplied by connecting between the hose and the hose or equipment.

  The intermediate tubular member has a first inner sphere-shaped portion whose outer surface is spherically bulged at one end, and the first tubular member is inserted with the first inner sphere-shaped portion and the central axis of the first tubular member A first inner spherical surface portion having an outwardly extending opening having a central axis that is appropriately angled with respect to the first inner spherical surface portion and the first inner spherical surface portion forming a spherical pair. Yes.

Furthermore, as a pipe joint having a simple structure and low manufacturing cost, a spherical ring body having at least an outer periphery formed into a spherical shape inside a cylindrical case body is fitted so as to be axially slidable and rotatable slidable An expandable flexible pipe joint has been invented in which the outer peripheral surface of the spherical ring body and the inner surface of the cylindrical case body are held in a watertight state (see, for example, Patent Document 3).
JP 2004-92699 A JP 2003-240174 A Japanese Patent Laid-Open No. 2001-200968

  However, since the flexible pipe joint according to Patent Document 1 is connected to a sleeve made of a synthetic resin that elastically deforms both pipe bodies, even if it is suitable for a drain pipe having a relatively low water pressure, When applied to a tube, there is a concern that the sleeve expands. If the thickness of the sleeve is increased to withstand high pressure, the bending performance may be impaired.

  Further, in the flexible pipe joint according to Patent Document 2, the flow path is refracted, and flow loss is likely to occur. A pipe joint whose flow path is gently curved is required. Furthermore, when the flexible pipe joint according to Patent Document 2 is used for a drain pipe, there is a problem that it is not possible to avoid the accumulation of sludge in the hollow portion in the refracting portion.

  The expansion / contraction flexible pipe joint according to Patent Document 3 similarly requires a pipe joint in which the flow path is refracted and the flow path is gently curved. And when used for a drain pipe, there exists a problem that it cannot avoid that sludge accumulates in the hollow part in the said refractive part. Furthermore, since the expansion / contraction flexible pipe joint according to Patent Document 3 does not use packing or the like, there is a problem that the sealing performance is poor.

  This invention is made | formed in view of the above subjects, and it aims at providing the pipe joint which has the flexibility which was excellent in the sealing performance while the flow path curved gently.

  In order to satisfy the above-mentioned object, the inventor provides a pair of annular flanges at both ends of a flexible tube main body so as to be integrated, and a plurality of spheres held on the respective outer peripheral surfaces of the pair of annular flanges The pair of annular flanged tube main bodies is housed in a holding body, and each of the pair of annular flanges has a structure in which a sphere rolls along the inner wall surface of the holding body. A pipe joint was invented.

  (1) A pipe joint for connecting a first pipe having a first flange and a second pipe having a second flange, a flexible tubular pipe body, and one end of the pipe body An annular first flange connected to the first flange; provided on the other end of the pipe body; connected to the second flange; and the annular flange A plurality of spheres held on the outer peripheral surfaces of the first flange and the annular second flange, and the tube main body, the annular first flange, the annular second flange, and the plurality of spheres are accommodated. And the annular first flange and the annular second flange are formed by rolling the spherical body along an inner wall surface of the holding body, respectively. The posture to the body can be changed. Pipe fitting and.

  The pipe joint according to the present invention is a pipe joint for connecting the first pipe and the second pipe, and the first pipe has a first flange and the second pipe has a second flange. For example, rigid pipes are used for the first pipe and the second pipe. The rigid tube may be a metal tube, a hard synthetic resin tube, or a hard elastic rubber tube. The first flange and the second flange preferably have a disk shape, and may be a quadrilateral or more polygonal plate. For example, the first flange and the second flange may be fixed to the respective pipe ends of the first pipe and the second pipe by welding, and are coupled to the pipe ends of the first pipe and the second pipe with pipe screws, respectively. May be.

  A pipe joint according to the present invention includes a flexible tubular pipe body, an annular first flange provided on one end side of the pipe body, and an annular first body provided on the other end side of the pipe body. 2 flanges. For example, the tube body may be a bellows formed of a synthetic resin, and a fluororesin is preferably used. For example, flanges are formed at both ends of the bellows, one flange of the bellows is sandwiched and connected by an annular first flange and a first flange, and the other flange of the bellows is an annular second flange. And may be sandwiched and connected by the second flange. Further, for example, the tube main body may be a metal bellows, and an annular first flange and an annular second flange may be provided by welding at both ends of the metal bellows.

  Further, for example, the tube body may be a rubber tube, and an annular first flange and an annular second flange may be provided at both ends of the rubber tube by the elastic force of the rubber tube. An annular first flange and an annular second flange may be provided by being bonded to both ends of the rubber tube. Further, for example, flanges may be formed at both ends of the rubber tube, and one flange of the rubber tube may be sandwiched and connected by the annular first flange and the first flange. The flange may be connected by being sandwiched between the annular second flange and the second flange.

  The first annular flange is connected to the first flange, and the second annular flange is connected to the second flange. For example, in the annular first flange, a plurality of female nails are formed on the contact surface of the first flange, a plurality of screw mounting holes are formed in the first flange, and the annular first flange and the first flange are hexagonal. It is fixed and connected with a fastener such as a bolt. Similarly, in the annular second flange, a plurality of female nails are formed on the contact surface of the second flange, and a plurality of screw mounting holes are formed in the second flange. Two flanges are fixed and connected by a fastener such as a hexagon bolt. And in these connection parts, it is possible to provide packing.

  The pipe joint according to the present invention includes a plurality of spheres held on the outer peripheral surfaces of the annular first flange and the annular second flange. For example, conical recesses are provided at positions that are divided into four at equal intervals on the outer peripheral surfaces of the first annular flange and the second annular flange, and four spheres are provided in the four conical recesses. You may make it hold | maintain. Also, for example, an annular arc groove may be provided on the outer peripheral surface of each of the annular first flange and the annular second flange, and a plurality of spheres may be held so as to fill up the annular arc groove. Good. From the viewpoint of wear resistance, the sphere is preferably a steel ball.

  A pipe joint according to the present invention includes a pipe body, an annular first flange, an annular second flange, and a cylindrical holding body that houses a plurality of spheres. For example, the outer shape of the holding body may be formed of a rectangular polygonal column including a rectangular prism, or may be formed of an expanded cylinder having a diameter at the middle portion larger than the diameter at both ends. Preferably, it is formed of a cylinder.

  After the tube main body, the annular first flange and the annular second flange are accommodated in the holding body, for example, a plurality of spheres are inserted from through holes provided in the outer periphery of the holding body, and the annular first flange is inserted. A plurality of spheres are accommodated on the outer peripheral surfaces of the first flange and the annular second flange. Thereafter, the through hole is sealed with a screw.

  The annular first flange and the annular second flange can change the posture with respect to the holding body by rolling the sphere along the inner wall surface of the holding body.

  In such a pipe joint, in a state where the first flange is connected to the annular first flange and the second flange is connected to the annular second flange, the first pipe and the second pipe are: Each can change the posture with respect to the holding body. Moreover, the 1st piping and 2nd piping are connected by the cylindrical pipe | tube main body which has flexibility.

  In the pipe joint according to the present invention, since the first pipe and the second pipe are connected by a flexible tubular pipe body, the flow path is gently bent without being refracted as in the prior art. There is an advantage that the occurrence of flow loss can be reduced. In addition, if the inner diameters of the first pipe, the second pipe, and the pipe main body are made equal, there will be no depression at the connecting part as in the conventional case, so sludge accumulates in the depression when used in a drain pipe. Can be avoided. Furthermore, in order to improve sealing performance, packing can be used for both connecting portions.

  (2) In the pipe joint according to (1), the portion of the inner wall surface of the holding body that accommodates the annular first flange is centered on the first point on the central axis of the holding body. The portion of the inner wall surface of the holding body that accommodates the annular second flange is defined by a spherical surface that is centered on a second point on the central axis of the holding body. Pipe fittings.

  The inner wall surface of the holding body is formed with a spherical surface centered on the first point on the central axis of the holding body, and the spherical surface centered on the second point on the central axis of the holding body. ing. The first point and the second point on the central axis of the holding body have a predetermined interval. The spherical surface centered on the first point and the spherical surface centered on the second point preferably have the same radius, but may have different radii.

  The annular first flange is configured such that the posture with respect to the holding body can be changed by rolling a plurality of spheres along a spherical surface centered on the first point on the central axis of the holding body. The annular second flange is configured such that the attitude of the sphere with respect to the holding body can be changed by rolling along a spherical surface centered on the second point on the central axis of the holding body.

  “A portion of the inner wall surface of the holding body that accommodates the annular first flange” includes an annular first flange and a portion that accommodates a plurality of spheres held by the annular first flange. A portion for accommodating a portion of the tube main body extending in the axial direction from the annular first flange is included. Further, “the portion of the inner wall surface of the holding body that accommodates the annular first flange” may include a first flange connected to the annular first flange, and extends in the axial direction from the first flange. One part of the first piping to be used may be included.

  “A portion of the inner wall surface of the holding body that accommodates the annular second flange” includes a portion that accommodates the annular second flange and the plurality of spheres held by the annular second flange. It includes a portion that accommodates a portion of the tube body that extends axially from the annular second flange. Furthermore, “the portion of the inner wall surface of the holding body that accommodates the annular second flange” may include a second flange connected to the annular second flange, and extends in an axial direction from the second flange. One part of the second pipe may be included.

  “The portion that accommodates the annular first flange is defined by a spherical surface centered on the first point” means that the annular first flange and the holding body constitute a spherical sliding pair. The annular first flange may allow a swaying motion and a tilting motion with respect to the holding body about the first point.

  “The portion that accommodates the annular second flange is defined by a spherical surface that is centered on the second point” means that the annular second flange and the holding member constitute a spherical sliding pair. The annular first flange may allow a swaying motion and a tilting motion with respect to the holding body around the second point.

  In the pipe joint configured in this manner, the annular first flange and the annular first flange housed in the holding body are such that the center point of each spherical motion is the first on the central axis of the holding body. A spherical surface centered on the point and a spherical surface centered on the second point on the central axis of the holding body, respectively, and the center point of the spherical motion in the annular first flange and in the annular second flange The distance from the center point of the spherical motion is kept constant. The intersecting angle between the central axis of the first pipe connected to the annular first flange and the central axis of the second pipe connected to the annular second flange is freely set in the three-dimensional space.

  (3) In the pipe joint according to (1) or (2), the outer circumferential surface of the annular first flange and the annular second flange has a recess for holding the sphere at predetermined intervals. A pipe joint characterized by being formed.

  In the first annular flange and the second annular flange, for example, four recesses are formed at equal intervals on each outer peripheral surface, and a sphere is held in the four recesses, whereby the annular first flange is formed. The center point of each spherical motion of the 1 flange and the annular second flange is stable.

  In the annular first flange and the annular second flange, it is preferable that three or more recesses are formed in each outer peripheral surface at “equal intervals”, and the annular first flange and the annular second flange are formed. The center point of each spherical motion at the two flanges is stable. For example, the recess in which the sphere is held may be formed in a conical shape or may be formed in a hemispherical shape.

  Thus, the pipe joint of the present invention can stabilize the center point of each spherical motion with the minimum number of spheres in the annular first flange and the annular second flange.

  (4) The pipe joint according to any one of (1) to (3), wherein the pipe body is a bellows.

  The pipe body has a compressive stress acting on one of its outer circumferences, and a tensile stress acts on the other outer circumference, so that a pipe that can expand and contract in the axial direction is preferable, and a bellows may be used as such a pipe body. . This bellows may be formed of a synthetic resin or a metal. For example, the bellows may include an inner bellows disposed as an inner tube and an outer bellows disposed as an outer tube, and may include a vibration damping tube filled with an elastic material between the inner bellows and the outer bellows. . Further, the valley diameter of the outer periphery of the bellows may be gripped by a ring so as to resist the fluid pressure in the bellows. Furthermore, it is also possible to set the wall thickness appropriately so as to resist the fluid pressure in the bellows.

  (4) The pipe joint according to any one of (1) to (3), wherein the pipe body is a rubber pipe.

  The pipe body has a compressive stress acting on one of its outer circumferences and a tensile stress acting on the other of its outer circumferences. Therefore, a pipe that can expand and contract in the axial direction is preferable. A rubber pipe is used as such a pipe body. Good. For example, this rubber tube is a so-called steel wire reinforced hose (ie, a pipe body) in which a stainless steel wire is wound in a knitted or spiral shape between an inner surface layer and an outer surface layer mainly composed of rubber or thermoplastic elastomer. May be included. Further, for example, the rubber tube may include a reinforcing hose (that is, a tube body) in which a tough fiber body is disposed as a reinforcing material between the inner surface layer and the outer surface layer.

  The thickness of the pipe joint of the present invention can be appropriately set so as to resist the fluid pressure in the pipe body. Further, the pipe joint of the present invention has an advantage that the occurrence of a flow loss can be reduced because the flow path is gently bent without being refracted unlike a pipe joint using a conventional spherical plain bearing. And when it is used for a drain pipe, it can avoid that sludge accumulates in a hollow part. Furthermore, in order to improve sealing performance, a packing can also be used for a connection part.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a front view showing an embodiment of a pipe joint according to the present invention, in which one side of a center line is a cross-sectional view. FIG. 2 is a configuration diagram of the pipe joint according to the embodiment, FIG. 2 (A) is a cross-sectional view of the pipe joint, and FIG. 2 (B) is a right side view of FIG. 2 (A). FIG. 2B is a partial cross section.

  FIG. 3 is a front view of the pipe joint according to the embodiment in a state in which an expansion pipe joint as a connecting pipe is connected. In FIG. 3, the holding body of the pipe joint according to the embodiment is shown in cross section. FIG. 4 is a front view of the expansion joint connected to the pipe joint according to the embodiment, and shows a cross-sectional view of one side of the center line.

  Initially, the structure of the pipe joint of one Embodiment by this invention is demonstrated.

  In FIG. 1, the first pipe 10 and the second pipe 20 are arranged on both sides of the pipe joint 30. The first pipe 10 has a first flange 11. The second pipe 20 has a second flange 21.

  More specifically, a pipe taper male thread is formed at the pipe end of the first pipe 10, a pipe taper female thread is formed at the center of the first flange 11, and the first flange 11 is threaded at the pipe end of the first pipe 10. Are combined. Similarly, a pipe taper male thread is formed at the pipe end of the second pipe 20, a pipe taper female thread is formed at the center of the second flange 21, and the second flange 21 is screwed to the pipe end of the second pipe 20. Yes.

  In FIG. 1, an annular first flange 31 is connected to the first flange 11, and an annular second flange 32 is connected to the second flange 21. More specifically, a plurality of female knives 31 a are formed in the annular first flange 31, and a plurality of screw attachment holes 11 a are formed in the first flange 11, and the annular first flange 31 and the first flange 11 are formed. Is fixed with hexagon bolts 4. Similarly, a plurality of female nails 32a are formed in the annular second flange 32, a plurality of screw mounting holes 21a are formed in the second flange 21, and the annular second flange 32 and the second flange 21 are hexagon bolts. 4 is fixed.

  In FIG. 1, a cylindrical tube body 33 is flexible. An annular first flange 31 is provided on one end side of the tube body 33. An annular second flange 32 is provided on the other end side of the tube body 33. The tube body 33 is a bellows formed of a synthetic resin made of a fluororesin. The bellows is also called a bellows tube or a corrugated tube, and is provided with corrugated pleats on a cylindrical outer periphery, and has elasticity and flexibility. In FIG. 1, in order to resist the fluid pressure in the pipe body 33, the valley diameter of the outer periphery of the pipe body 33 is held by a ring 33a.

  In FIG. 1, a flange 3a and a flange 3b are provided at both ends of the pipe body 33, respectively. One flange 3a of the pipe body 33 is sandwiched and connected by the annular first flange 31 and the first flange 11, and the other flange 3b of the pipe body 33 is the annular second flange 32 and the second flange 21. It is pinched and connected.

  In FIG. 1, a plurality of spheres 34 are held on the outer peripheral surfaces of an annular first flange 31 and an annular second flange 32. An annular first flange 31, an annular second flange 32, and a pipe body 33 are integrally stored in a cylindrical holding body 35 together with a plurality of spherical bodies 34.

  As shown in FIG. 2, the portion of the inner wall surface of the holding body 35 that accommodates the annular first flange 31 is a spherical surface S <b> 1 centered on the first point B <b> 1 on the central axis G <b> 4 of the holding body 35. It is stipulated in. Similarly, the portion of the inner wall surface of the holding body 35 that accommodates the annular second flange 32 is defined by a spherical surface S2 centered on the second point B2 on the central axis G4 of the holding body 35. .

  In FIG. 2, the first point B1 and the second point B2 have a predetermined distance d, and the radius r1 of the first spherical surface S1 and the radius r2 of the second spherical surface S2 are the same. Further, when the central axis G3 of the tube main body 33 is in a straight line state, the central axis G3 of the tube main body 33 shares the central axis G4 of the holding body 35.

  Furthermore, as shown in FIG. 1, when the central axis G3 of the pipe main body 33 is in a straight line state, the central axis G1 of the first pipe 10 and the central axis G2 of the second pipe 20 are the central axis G3 of the pipe main body 33. Are connected so as to be in a straight line.

  In FIG. 2, the first spherical surface S <b> 1 and the second spherical surface S <b> 2 communicate with each other in the holding body 35, and open at both end faces of the holding body 35. The first spherical surface S1 and the second spherical surface S2 each form a partial spherical surface.

  In FIG. 2, a plurality of hemispherical recesses 31 b are formed on the outer peripheral surface of the annular first flange 31. Similarly, a plurality of hemispherical depressions 32 b are formed on the outer periphery of the annular second flange 32. The plurality of spheres 34 are held in the depressions 31b and 32b and can roll.

  In FIG. 2, four spheres 34 are held at equal intervals on the outer peripheral surfaces of the annular first flange 31 and the annular second flange 32. An annular first flange 31 and an annular second flange 32 are used as inner rings, a holding body 35 is used as an outer ring, and a plurality of spheres 34 are interposed between the inner ring and the outer ring, whereby the pipe joint 30 is a rolling ball bearing. It has the same function.

  In FIG. 2, three or more depressions 31 b and 32 b in which a plurality of spheres 34 are held at equal intervals may be formed on the outer peripheral surfaces of the annular first flange 31 and the annular second flange 32. Instead of the hemispherical depressions 31b and 32b, conical depressions may be used.

  As shown in FIG. 2, female screw holes 35 a penetrating from the outer circumferential surface of the holding body 35 to the first spherical surface S <b> 1 and the second spherical surface S <b> 2 are formed. The spheres 34 are sequentially inserted from the female screw hole 35a toward the recesses 31b and 32b. After all the spheres 34 have been introduced, the female screw holes 35a are sealed with hexagon socket bolts (not shown) to prevent the plurality of spheres 34 from falling off.

  Note that the radius of the opening formed on both end faces of the holding body 35 is such that the plurality of spheres 34 after dropping do not fall off even if the annular first flange 31 and the annular second flange 32 are inclined. Designed to.

  And the annular | circular shaped 1st flange 31 enables change of the attitude | position with respect to the holding body 35, when the some spherical body 34 rolls along 1st spherical surface S1. Similarly, the annular second flange 32 is configured such that the posture with respect to the holding body 35 can be changed by rolling the plurality of spheres 34 along the second spherical surface S2.

  Next, the operation of the pipe joint according to the present invention will be described.

  As shown in FIG. 2, the annular first flange 31 constitutes a spherical pair even with the first spherical surface S <b> 1 serving as the inner wall surface of the holding body 35 via a plurality of spherical bodies 34. The annular second flange 32 constitutes a spherical pair even with the second spherical surface S2 serving as the inner wall surface of the holding body 35 via a plurality of spherical bodies 34.

  As shown in FIG. 2, the pipe joint 30 has a constant distance d between the first point B1 in the annular first flange 31 and the second point B2 in the annular second flange 32. Is maintained. As shown in FIG. 3, the first pipe 10 connected to the annular first flange 31 and the second pipe 20 connected to the annular second flange 32 are refracted and arranged in an intersecting manner. The first pipe 10 and the second pipe 20 are gently connected with a flexible tubular pipe body 33.

  As shown in FIG. 3, the pipe joint 30 is connected to the central axis G <b> 1 (see FIG. 1) of the first pipe 10 connected to the annular first flange 31 and the annular second flange 32. The intersecting angle with the central axis G2 (see FIG. 1) of the second pipe 20 is freely set in the three-dimensional space.

  In such a pipe joint, since the first pipe and the second pipe are connected by a flexible pipe body, the flow path is gently bent without being refracted as in the prior art. There is an advantage that the occurrence of flow loss can be reduced. In addition, if the inner diameters of the first pipe, the second pipe, and the pipe main body are made equal, there will be no depression at the connecting part as in the conventional case, so sludge accumulates in the depression when used in a drain pipe. Can be avoided. Furthermore, in order to improve sealing performance, a packing can also be used for a connection part.

  Next, the structure of the expansion pipe joint as a connecting pipe connected to the pipe joint according to the present invention will be described.

  As shown in FIG. 4, the telescopic pipe joint 40 has a first flange 11 that can be connected to an annular first flange 31 (see FIG. 3) in the pipe joint 30 at one end in the axial direction. The second flange 21 is connectable to the annular second flange 32 (see FIG. 3) of the pipe joint 30 at the other end. A joint pipe 6 that can extend and contract in the axial direction is provided between the first flange 11 and the second flange 21.

  As shown in FIG. 4, the joint pipe 6 is a combination of a small-diameter rigid pipe 61 and a large-diameter rigid pipe 62. The small-diameter rigid tube 61 and the large-diameter rigid tube 62 are slidably fitted with a coaxial core. As the small-diameter rigid tube 61 and the large-diameter rigid tube 62, for example, a metal tube or a hard synthetic resin tube is used.

  The pipe end of the first pipe 10 to which the first flange 11 is attached is connected to the pipe end of the small-diameter rigid pipe 61 by the threaded pipe joint 5. The pipe end of the second pipe 20 to which the second flange 21 is attached is joined to one pipe end of the tapered pipe 23. The other tube end of the tapered tube 23 is joined to the tube end of the large-diameter rigid tube 62.

  The diameter of one pipe end of the tapered pipe 23 is equal to the diameter of the pipe end of the second pipe 20, and the diameter of the other pipe end of the tapered pipe 23 is equal to the diameter of the pipe end of the rigid pipe 62. At both pipe ends of the taper pipe 23, the second pipe 20 and the rigid pipe 62 are joined together so as to have a coaxial center.

  As shown in FIG. 4, an annular member 6 a is provided at the pipe end of the large-diameter rigid pipe 62. The annular member 6a is internally provided with a seal member 6s such as an O-ring that slides and adheres to the outer peripheral surface of the small-diameter rigid tube 61.

  As shown in FIG. 4, the joint pipe 6 is further provided with a threaded pipe joint 64. A male thread is formed at one end of the threaded pipe joint 64. One end of the threaded pipe joint 64 is fitted into the annular member 6a, and the threaded pipe joint 64 and the annular member 6a are fixed by the cap nut 63. The large-diameter rigid pipe 62 and the threaded pipe joint 64 are integrated.

  An annular member 6 c is provided at the other end of the threaded pipe joint 64. The annular member 6c is internally provided with a seal member 6s such as an O-ring that slides on and adheres to the outer peripheral surface of the small-diameter rigid tube 61.

  An annular member 6b is provided on the outer periphery of the small-diameter rigid tube 61 so as to be positioned between the annular member 6a and the annular member 6c. The annular member 6b is provided with a sealing member 6t such as an O-ring that slides on and closely contacts the inner peripheral surface of the threaded pipe joint 64.

  The annular member 6b functions as a stopper that limits the amount of expansion and contraction in the axial direction between the small-diameter rigid tube 61 and the large-diameter rigid tube 62. That is, when the joint pipe 6 contracts, the annular member 6b provided in the small-diameter rigid pipe 61 contacts the annular member 6a provided in the large-diameter rigid pipe 62, and the joint pipe 6 does not contract any further. . On the other hand, when the joint pipe 6 extends, the annular member 6b provided in the small-diameter rigid pipe 61 contacts the annular member 6c provided in the large-diameter rigid pipe 62, and the joint pipe 6 does not extend any further. .

  Further, as shown in FIG. 4, a plurality of through holes 6h are formed at the location of the small-diameter rigid tube 61 located near the annular member 6b and on the annular member 6c side. The through hole 6h communicates with a space closed by the annular member 6b and the annular member 6c. Therefore, when the expansion joint 40 contracts, the fluid closed in the expansion pipe joint 40 can flow out into the space closed by the annular member 6b and the annular member 6c.

  As shown in FIG. 3, the expansion pipe joint 40 configured in this way is connected to the flexible pipe joint that bears the bent portion by connecting the expansion pipe joint 40 between two pipe joints 30 that are separated from each other. It is easy to connect pipes that are separated from each other by connecting pipes that carry the characteristics.

  Although the expansion joint 40 according to the present invention has been described as connecting two spaced pipe joints 30, the pipe joint 30 according to one embodiment of the present invention is not limited to the expansion joint 40. . The pipe joint according to the present invention may be connected to, for example, a rigid pipe that does not expand and contract in the axial direction.

It is a front view showing one embodiment of a pipe joint by the present invention. It is a block diagram of the pipe joint by the said embodiment. It is a front view in the state where the expansion pipe joint as a connecting pipe was connected to the pipe joint by the said embodiment. It is a front view of the expansion pipe joint connected to the pipe joint by the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 1st piping 11 1st flange 20 2nd piping 21 2nd flange 30 Pipe joint 31 1st annular flange 31b * 32b hollow 32 2nd annular flange 33 Pipe body (bellows)
34 Sphere 35 Holding body B1 First point B2 Second point G4 Central axis (central axis of the holding body)
S1 spherical surface (spherical surface with the first point as the center)
S2 Spherical surface (spherical surface centered on the second point)

Claims (5)

A pipe joint for connecting a first pipe having a first flange and a second pipe having a second flange,
A tubular body having flexibility,
An annular first flange provided on one end of the pipe body and connected to the first flange;
An annular second flange provided on the other end of the tube body and connected to the second flange;
A plurality of spheres held on outer circumferential surfaces of the annular first flange and the annular second flange;
A cylindrical holder that houses the tube main body, the annular first flange, the annular second flange, and the plurality of spheres;
Each of the annular first flange and the annular second flange can change its attitude relative to the holding body by rolling the spherical body along an inner wall surface of the holding body. Pipe fittings. In the pipe joint according to claim 1,
The portion of the inner wall surface of the holding body that accommodates the annular first flange is defined by a spherical surface centered on a first point on the central axis of the holding body,
A portion of the inner wall surface of the holding body that accommodates the annular second flange is defined by a spherical surface centering on a second point on the central axis of the holding body. In the pipe joint according to claim 1 or 2,
A pipe joint having a recess for holding the sphere at predetermined intervals is formed on the outer peripheral surfaces of the annular first flange and the annular second flange. In the pipe joint according to any one of claims 1 to 3,
The pipe joint is characterized in that the pipe body is a bellows. In the pipe joint according to any one of claims 1 to 3,
The pipe joint is characterized in that the pipe body is a rubber pipe.

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