JP2012219867A - Insertion-type pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a connecting pipe from being pulled off even if a force in the pull-off direction is applied to the connecting pipe, to improve long-term sealing performance, and to make visible the execution of proper connecting work.SOLUTION: An insertion-type pipe joint comprises: a joint body 10 having a socket 11 to which a connecting pipe is inserted; a cylindrical packing 20 arranged so that its one end is supported to the entrance side of the socket 11; and a locking means 30 provided at the back side of the packing 20 and axially slidable along the inner peripheral surface of the socket 11 in order to make the connecting pipe engaged therewith. The locking means 30 comprises: a spacer 31 slidable in the axial direction of the socket 11 and formed with a tapered surface 32 having a shape narrowed in the entrance direction of the socket 11; and a locking member 34 whose outer surface 36 is internally in contact with the tapered surface 32 and whose inner diameter side is engaged with the outer peripheral surface of the connecting pipe. The insertion-type pipe joint is provided with a color changing means 60 that changes a color when receiving the pressing force between a support member 55 and the packing 20.

Description

  The present invention relates to a pipe joint used for connecting various pipes, and more particularly, to a plug-in pipe joint that can be easily connected without skill when connecting.

Conventionally, it has been performed that a screw is processed at an end of a steel pipe and screwed into a pipe joint, or a steel pipe and a pipe joint are welded. In recent years, it has become difficult to secure screw processing engineers and welding engineers at the construction site, and various types of easily connected pipe joints that can be easily installed without skills are proposed and put into practical use. ing.
For example, Patent Document 1 discloses a joint body in which a tapered surface that is narrowed toward the upstream side in the insertion direction of the connecting pipe is formed on the inner periphery of the receiving portion, and an inner diameter portion that is inscribed in the tapered surface. Is a plug-in type pipe joint having a retaining member engaged with the outer peripheral surface of the connecting pipe and a lip packing housed in the joint body. In this case, when the connecting pipe is inserted, the lip portion of the lip packing is brought into close contact with the outer peripheral surface of the connecting pipe, and when water pressure is further applied, the lip portion is pressed against the outer peripheral surface of the connecting pipe to generate a sealing pressure. is there. Further, when the connecting pipe is pulled in the pulling direction, the outer diameter portion of the retaining member comes into contact with the tapered side of the tapered surface, and the engaging teeth are caused to bite into the outer peripheral surface of the connecting pipe.

Further, Patent Document 2 discloses an outer cylinder in which a tapered surface that is narrowed toward the upstream side in the insertion direction of the connecting pipe is formed on the inner periphery of the receiving port, a lock ring accommodated in the outer cylinder, A pipe joint having an O-ring and a spring held in compression is described. The spring is held in a compressed state between a spring holder in which a flange is formed on the outside on the opposite side and a support ring that is regulated in a pull-out direction by a support ring regulating portion formed on the tip of the cut.
When the connecting pipe is inserted, the support ring is disengaged from the support ring restricting portion, and the spring is extended to compress the O-ring, and the lock ring is bitten into the outer peripheral surface of the connecting pipe. And since the O-ring is forcibly compressed, the sealing effect is said to be enhanced. Furthermore, the outer cylinder has a confirmation window through which the lock ring can be seen, and the completion of the work can be visually confirmed.

  Further, Patent Document 3 has a plurality of balls mounted on a joint member, a coil spring held in a compressed state, and a packing disposed in the vicinity of the inlet of the joint, and when the connection pipe is inserted, the connection pipe A one-touch plug-in joint for a corrugated tube is described in which a ball is locked to the outer peripheral surface of the tube and a coil spring extends to press the packing.

In Patent Document 4, a seal ring for sealing a pipe, a presser ring having a tapered surface whose one end surface is in contact with the seal ring and whose diameter increases toward the other end, and a tapered surface of the presser ring are fitted. A plastic pipe joint is described having a bite ring with a claw that bites into the outer surface of the pipe.
These Patent Documents 1 to 4 can be connected only by inserting a pipe to be connected into a pipe joint.

  Furthermore, although it is not connectable just by inserting a pipe, in Patent Document 5, a pressure-sensitive paper is interposed between the inner surface of the flange portion of the union nut and the pressing ring so that the tightening torque of the union nut can be visually confirmed. A resin pipe joint is described (see paragraph 0026).

JP 2010-0665745 A JP 2003-106490 A Japanese Utility Model Publication No. 4-117985 Japanese Unexamined Patent Publication No. 63-23082 JP 2002-357289 A

However, in Patent Document 1, the seal surface pressure is generated by the elastic force of the lip of the lip packing and the fluid pressure applied to the back surface of the lip. Therefore, for example, when the fluid is at a relatively low pressure, such as city gas, sealing is performed only by the elastic force of the lip packing, and there is a concern that the sealing performance may be deteriorated due to deterioration of the rubber lip packing in the long term. . The thing of patent document 2 makes the resin pipe the connection object, and is generally used for indoor water supply / hot water supply piping. However, when this is used for outdoor piping, rainwater or the like may enter from the outside of the pipe joint, and the lock ring may corrode.
In particular, in Patent Documents 1 and 2, when a force in the pulling direction is applied, the pulling-out member is prevented by the action of the retaining member in contact with the tapered surface, but there is no influence on the seal surface pressure with the tube. Does not reach. For example, in an environment where the connection pipe repeatedly expands and contracts due to a temperature difference of the outside air temperature, such as a ground exposed pipe, there is a concern about long-term sealing performance.

Further, in Patent Document 3, the corrugated tube is a connection target, and when a force in the pulling direction is applied to the corrugated tube, there is a problem that the corrugated irregularities are deformed and the outer diameter contracts to reduce the seal surface pressure. The thing of patent document 4 makes the plastic pipe the connection object, and when the force of a drawing direction is added to a plastic pipe, a pipe will be stretched ductively and the outer surface diameter of a pipe will contract, and the seal surface pressure will fall. was there.
Furthermore, although Patent Documents 1, 3, and 4 can be connected by simply inserting the tube, whether or not the tube has been inserted to a predetermined position for sufficiently exhibiting sealing performance and pull-out prevention There was a problem that could not be confirmed.

  The thing of patent document 5 can connect only the special tube which has an enlarged diameter part in one end, and also involves the troublesome work of tightening a union nut.

  The present invention has been made to solve such problems. The object of the present invention is to prevent the pipe from being pulled out even when a force in the pulling direction is applied to the connecting pipe as described above. In addition, an object of the present invention is to provide a plug-in type pipe joint that improves long-term sealing performance and can visually recognize that an appropriate connection operation has been performed.

The present invention has been made to solve the above problems, and the gist of the present invention is a joint body having a receiving port into which the tip of a connecting pipe is inserted, and a transparent body fixed to the inlet side of the receiving port. A cylindrical packing whose one end is supported by a support member, and a retaining means which is disposed on the back side of the packing, is engaged with the outer peripheral surface of the connecting pipe and is slidable in the axial direction of the receiving port And a pressing means that is disposed on the back side of the retaining means and is capable of pressing the retaining means toward the inlet inlet when the connecting pipe is inserted into a predetermined position, and further includes the support member and the packing. An insertion-type pipe joint is provided with a discoloring means that discolors when subjected to a pressing force therebetween.
According to the present invention, since the retaining means engaged with the outer peripheral surface of the connecting pipe is disposed on the back side of the packing and can slide in the axial direction of the receiving port, a force in the pulling direction is applied to the connecting pipe. In this case, the retaining means acts to press the packing and increase the seal surface pressure. Therefore, even when a pulling direction force is applied to the connecting pipe, it is possible to prevent the pipe from being pulled out and improve long-term sealing performance. Further, since the packing is disposed at the receiving port inlet, the packing can secure the sealing performance with the connection pipe and can prevent intrusion of rainwater or the like from the outside. Furthermore, the operator can easily recognize that the connection pipe has been inserted into a predetermined position and normal connection has been completed.
In the present invention, the color changing means may be a pressure sensitive paper or a microcapsule.

  In the present invention, the retaining means includes a spacer that is slidable in the axial direction of the receiving port and has a tapered surface that is tapered toward the receiving port, and an outer surface portion that is inscribed in the tapered surface. It is preferable that the inner diameter portion includes a retaining member engaged with the outer peripheral surface of the connection pipe. Further, in the invention according to claim 3, the retaining member includes a plurality of retaining blade members having a blade portion in which an outer surface portion is inscribed in the tapered surface and bites into an outer peripheral surface of the connection pipe on an inner side, and an inner periphery from the outer peripheral surface. The cylindrical holding member is preferably formed with an opening that penetrates the surface and supports the plurality of retaining blade members.

  In the invention according to claim 4, it is preferable that a thermally expandable packing is interposed between the outer periphery of the holding member and the inner periphery of the receiving port so that the holding member and the receiving port are concentric. According to this configuration, since the heat-expandable packing is arranged so that the holding member is concentric with the receiving port, the holding member can be inserted even when the connecting tube is inserted obliquely with respect to the receiving port. Without the eccentricity, it is possible to prevent the retaining blade member from falling off due to the eccentricity of the holding member.

  In the above invention, the pressing means includes a cylindrical spring guide having a flange portion at one end and a slit portion formed on the opposite side, a washer inserted into the spring guide from the tip of the slit portion, and the washer. A washer restricting portion that is regulated in the pulling direction and provided at the tip of the slit portion, a coil spring that is held in a compressed state between the flange portion and the washer, and an slit that is inserted through the inner peripheral surface of the spring guide It can comprise from the moving piece which regulates the diameter reduction to the inner peripheral side of a part.

  According to the present invention, since the retaining means engaged with the outer peripheral surface of the connecting pipe is disposed on the back side of the packing and can slide in the axial direction of the receiving port, a force in the pulling direction is applied to the connecting pipe. In this case, the retaining means acts to press the packing and increase the seal surface pressure. Therefore, even when a pulling direction force is applied to the connecting pipe, it is possible to prevent the pipe from being pulled out and improve long-term sealing performance. Further, since the packing is disposed at the receiving port inlet, the packing can secure the sealing performance with the connection pipe and can prevent intrusion of rainwater or the like from the outside. Furthermore, the operator can easily recognize that the connection pipe has been inserted into a predetermined position and normal connection has been completed.

It is a perspective view of the insertion type pipe joint of one form of the present invention. It is sectional drawing of the insertion-type pipe joint of FIG. 1, and is 1/4 sectional drawing which abbreviate | omitted the symmetrical part. It is a figure which shows the state in the middle of inserting the connection pipe in the insertion type pipe joint of FIG. It is a figure which shows the state which completed the connection of the connection pipe to the plug-in type pipe coupling of FIG. It is sectional drawing of the plug-in type pipe joint of 2nd embodiment of this invention, and is 1/4 sectional drawing which abbreviate | omitted the symmetrical part.

<First Example>
As shown in FIG. 1 and FIG. 2, the plug-in type pipe joint 1 is arranged such that a joint body 10 having a receiving port 11 into which a connecting pipe is inserted, and one end thereof is supported on the inlet side of the receiving port 11. A cylindrical packing 20 formed on the inner side of the packing 20 and a retaining means 30 for engaging with a connecting pipe 80 located on the inner side of the packing 20 and slidable in the axial direction along the inner peripheral surface of the receiving port 11. Become the Lord. FIG. 1 shows a socket-type plug-in joint for connecting connecting pipes on both sides. However, the present invention is not limited to this form, and various forms of general pipe joints such as elbows, cheeses, reducers, caps, etc. Can be made.

  In the receiving port 11, a step portion 13, a groove first circumference 15 at the inlet end, and a second circumferential groove 17 on the slightly rear side thereof are formed. A C-shaped first retaining ring 71 is fitted in the first circumferential groove 15 so that a support member 55 </ b> A for supporting one end of the packing 20 is engaged. Further, as will be described later, the second retaining ring 73 fitted in the second circumferential groove 17 prevents the retaining means 30 from coming out when the plug-in fitting 1 is exposed to high temperature and the packing 20 is burned out. It is for preventing.

The retaining means 30 includes a spacer 31 that is slidable in the axial direction of the receiving port 11 and formed with a tapered surface 32 that is tapered toward the inlet direction of the receiving port 11, and an outer surface portion 36 that is inscribed in the tapered surface 32. The inner diameter side includes a retaining member 34 engaged with the outer peripheral surface of the connecting pipe. The retaining member 34 has, for example, a plurality of retaining blade members 35 having a blade portion 37 in which the outer surface portion 36 is inscribed in the tapered surface 32 and bites into the outer peripheral surface of the connection pipe 80 inside, and penetrates from the outer peripheral surface to the inner peripheral surface. The cylindrical holding member 25 is formed with an opening 27 for supporting the plurality of retaining blade members 35. In this case, the blade portion 37 is slightly smaller than the size of the opening 27 and is allowed to move in the radial direction with respect to the opening 27, but the outer surface portion 36 of the retaining blade member 35 is slightly larger than the size of the opening 27. Therefore, the retaining blade member 35 is prevented from falling off to the inner diameter side.
The retaining member 34 may be a C-shaped member in which a blade portion is formed on the inner peripheral surface and a notch is formed at one place.

Further, a pressing means 40 is disposed on the back side of the retaining means 30. The pressing means 40 enables the retaining means 30 to be pressed toward the inlet side of the receiving port 11 when the connecting pipe 80 is inserted at a predetermined position.
More specifically, a cylindrical spring guide 41 having a flange portion 42 at one end and a slit portion 43 formed on the opposite side, a washer 45 inserted from the tip of the slit portion 43 into the spring guide 41, and a washer 45 Is inserted in the inner peripheral surface of the spring guide 41, a washer restricting portion 44 provided at the tip of the slit portion 43, a coil spring 46 held in a compressed state between the flange portion 42 and the washer 45. It is comprised from the moving piece 47 which regulates the diameter reduction to the inner peripheral side of the slit part 43. FIG.
The pressing means is not limited to the above-described form, and any pressing means may be used as long as the retaining means 30 can be pressed toward the inlet side of the receiving port 11 when the connecting pipe 80 is inserted at a predetermined position. For example, the washer 45 may be omitted, and the washer restricting portion 44 may be engaged with the receiving port 11, or the slit portion 43 and a part of the moving piece 47 may be connected and separated when the connecting pipe 80 is inserted. Such a form is also possible.

A ring-shaped thermally expandable packing 75 is fitted so as to contact the inner peripheral surface of the receiving port 11 and the outer peripheral surface of the holding member 25. Since the heat-expandable packing 75 is arranged so that the holding member 25 is concentric with the receiving port 11 in this way, for example, when the connecting tube 80 is inserted obliquely with respect to the receiving port 11 As described above, even when a force for decentering the holding member 25 is applied, the holding member 25 is not decentered, and the retaining blade member 35 can be prevented from falling off due to the eccentricity of the holding member 25. The thermal expansion packing 75 is made of synthetic rubber with expandable graphite interposed therein, and has a property of expanding to a volume several hundred times when exposed to a high temperature.
In addition, when handling a liquid fluid whose sealing performance is not questioned when exposed to high temperatures, considering only prevention of the retaining blade member 35 from falling off, an elastic ring biased toward the holding member 25 is provided with a plurality of retaining blade members. You may make it go around the outer surface of 35. In this case, since the retaining blade member 35 is biased toward the holding member 25, it also has an effect of facilitating biting into the connection pipe 80.

  A transparent support member 55 locked to the first retaining ring 71 is provided at the entrance of the receiving port 11, and a color changing means 60 is provided between the support member 55 and the packing 20. For example, the color changing means can be composed of pressure sensitive paper or microcapsules. For example, a microcapsule is obtained by encapsulating fine particles obtained by mixing a dye and a coloring material inside a capsule membrane material made of melamine resin, and has a property of developing color when a pressure is applied to the microcapsule.

  As shown in FIG. 3, when the connection pipe 80 is inserted into the plug-in type pipe joint 1, the tip of the connection pipe 80 comes into contact with the moving piece 47 through the packing 20 and the inner peripheral side of the retaining member 34. The inner diameter of the packing 20 is slightly larger than the maximum outer diameter of the connecting pipe 80 in order to reduce the insertion load of the connecting pipe 80 and prevent the inner peripheral surface of the packing 20 from being damaged at the tip of the connecting pipe 80. It is preferable to set. For further safety, it is preferable to provide a damage prevention sleeve that covers the tip of the connection pipe 80 at the inlet end of the receiving port 11 and slides in the back direction together with the pipe.

When the connection pipe 80 is further pushed in, as shown in FIG. 4, the moving piece 47 slides to the back side of the receiving port 11, the diameter reduction regulation of the slit portion 43 is removed, and the washer 45 jumps out of the washer regulation portion 44. At the same time, the coil spring 46 expands and the flange portion 42 presses the retaining member 34 via the thermal expansion packing 75. Since the retaining member 34 is reduced in diameter along the tapered surface 32, the blade portion 37 bites into the outer peripheral surface of the connecting pipe 80. Further, the packing 20 is pressed through the spacer 31 by the extension force of the coil spring 46. Therefore, the inner peripheral surface of the packing 20 is reduced in diameter to seal the outer peripheral surface of the connection pipe 80.
Further, since the discoloration means 60 is provided between the support member 55 and the packing 20, the discoloration occurs when the packing 20 is pressed, and the connection pipe 80 is inserted into a predetermined position and the normal connection is completed. An operator or the like can easily recognize.

  When connecting the connecting pipe 80 to the plug-in pipe joint 1, the operator's line of sight is placed at the inlet 11 of the plug-in pipe joint 1 and the tip of the connecting pipe 80. Since the discoloring means 60 of the plug-in pipe joint 1 is provided in the vicinity of the receiving port 11, the completion of connection can be visually recognized without changing the operator's line of sight.

  After the connection between the plug-in type pipe joint 1 and the connection pipe 80 is completed, when a force in the pulling direction is applied to the connection pipe 80, the retaining means 30 engaged with the outer peripheral surface of the connection pipe 80 is attached to the packing 20. Since it is arranged on the back side and is configured to be slidable in the axial direction of the receiving port 11, the retaining means 30 acts to press the packing 20 and increase the seal surface pressure. Therefore, even when a pulling direction force is applied to the connecting pipe 80, it is possible to prevent the pipe from being pulled out and improve the long-term sealing performance. Since the packing 20 is disposed at the inlet of the receiving port 11 and only one part is required as a sealing member, the cost of parts can be reduced, and the sealing performance with the connecting pipe 80 can be secured and rainwater and the like can be infiltrated from the outside. It is possible to achieve both prevention.

  When the plug-in fitting 1 is exposed to a high temperature due to a fire or the like, the packing 20 is burned out. At this time, the retaining means 30 receives the extension force of the coil spring 46 and is thus locked to the second retaining ring 73. The thermally expandable packing 75 expands and fills between the retaining means 30 and the flange portion 42. Therefore, even if a fire or the like occurs, there is no risk of leakage of the internal fluid.

  If the inner peripheral surface of the receiving port 11 and the outer peripheral surface of the spacer 31 are provided in a circular shape, the spacer 31 is allowed to move not only in the axial direction but also in the circumferential direction. Even after connecting the connecting pipe 80, since it can rotate between the inner peripheral surface of the receiving port 11 and the outer peripheral surface of the spacer 31, it becomes easy to adjust the direction of the elbow or cheese. In order to make sliding between the inner peripheral surface of the receiving port 11 and the outer peripheral surface of the spacer 31 easier, it is preferable to apply a lubricant such as silicon oil. Or when using for a drinking water piping, it is preferable to coat the material with small friction coefficients, such as a fluororesin.

<Second Example>
FIG. 5 shows a second embodiment. In addition, the same structure as 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits detailed description. As shown in the figure, the joint main body 10A of the plug-in type pipe joint 1A is formed with a male screw at an end portion, and a nut 19 is screwed together. The nut 19 is formed of a transparent resin material. Since the support member 55 is also transparent, the color change state of the color change means 60 can be visually recognized more easily.

  In the said embodiment, it is suitable for piping materials, such as a general purpose steel pipe, a lining steel pipe, and a composite pipe, especially the outdoor piping in which the concern of the expansion and contraction of a pipe | tube by external temperature or the influence of rainwater etc. is a concern. The fluid may be a gas liquid, but when used for a drinking water pipe, the anti-corrosion measure is applied to the retaining means 30 and the pressing means 40 using stainless steel or the like.

1, 1A: Plug-in type pipe joint 10, 10A: Fitting main body, 11: Receptor, 13: Stepped portion, 15: First circumferential groove, 17: Second circumferential groove, 19: Nut,
20: packing, 22: protrusion, 25: holding member, 27: opening,
30: retaining means, 31: spacer, 32: tapered surface, 34: retaining member, 35: retaining blade member, 36: outer surface portion, 37: blade portion,
40: pressing means, 41: spring guide, 42: flange portion, 43: slit portion, 44: washer regulating portion, 45: washer, 46: coil spring, 47: moving piece,
50: Thermal expansion packing, 55: Support member,
60: Discoloration means,
71: First retaining ring, 73: Second retaining ring, 75: Thermally expandable packing,
80: Connection pipe

Claims (6)

A joint body having a receptacle into which the tip of the connecting pipe is inserted;
A cylindrical packing having one end supported by a transparent support member fixed to the inlet side of the receiving port;
A retaining means that is disposed on the back side of the packing, is engaged with the outer peripheral surface of the connecting pipe and is slidable in the axial direction of the receiving port;
A pressing means that is arranged on the back side of the retaining means, and is capable of pressing the retaining means toward the inlet inlet when the connecting pipe is inserted into a predetermined position;
Furthermore, the plug-in type pipe joint is provided with a discoloration means that discolors when receiving a pressing force between the support member and the packing.   The plug-in type pipe joint according to claim 1, wherein the color changing means is pressure sensitive paper or a microcapsule.   The retaining means includes a spacer that is slidable in the axial direction of the receiving port and has a tapered surface that is tapered toward the receiving port, and an outer surface portion that is inscribed in the tapered surface and an inner diameter portion that is connected to the spacer. The plug-in type pipe joint according to claim 1 or 2, comprising a retaining member engaged with an outer peripheral surface of the pipe.   The retaining member includes a plurality of retaining blade members having an outer surface portion inscribed in the tapered surface and having an inner blade portion that bites into the outer peripheral surface of the connecting pipe, and the plurality of retaining members penetrating from the outer peripheral surface to the inner peripheral surface. The plug-in type pipe joint according to claim 3, comprising a cylindrical holding member in which an opening for supporting the blade member is formed.   The plug-in type according to claim 4, wherein a thermally expandable packing is interposed between the outer periphery of the holding member and the inner periphery of the receiving port so that the holding member and the receiving port are concentric. Pipe fittings. The pressing means includes a cylindrical spring guide having a flange portion at one end and a slit portion formed on the opposite side;
A washer inserted into the spring guide from the tip of the slit portion;
Restricting the washer in the pulling direction, and a washer restricting portion provided at the tip of the slit portion;
A coil spring held in a compressed state between the flange and the washer;
The plug-in type pipe joint according to any one of claims 1 to 5, further comprising a moving piece that is inserted into the inner peripheral surface of the spring guide and restricts the diameter of the slit portion toward the inner peripheral side. .

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