JP2005249140A - Pipe connecting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily perform the execution of work and maintenance by applying a structure for easily mounting and demounting an insertion body to be connected with a pipe body, to a joint main body by manual work while preventing water leakage. <P>SOLUTION: An O-ring 3 as a seal member for keeping the water-tightness is mounted between the joint main body 10 and the mounting part 2 of the insertion body 1 in a state of being kept into contact with each other, and a lock ring 20 having spring property is mounted on an inner periphery of the joint main body 10 in a state that its diameter can be expanded. A step part 7 for fitting the lock ring 20 is formed on an outer periphery of the mounting part 1 of the insertion body 1, and an inclined guide face 6 for guiding the lock ring 20 is formed on the step part 7. The lock ring 20 is fitted to the step part 7 at a screwing terminal end position of the insertion body 1, and the insertion body 1 is connected with the joint 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a structure for connecting piping for passing water, hot water, other various liquids, city gas, propane gas, and other various gases.

  In general, a joint that is screw-coupled is used for connecting pipes, and when connecting, a sealing tape is wound around a thread portion of the joint or a sealing agent is applied.

  Conventionally, metal pipes such as lead pipes and galvanized pipes have been frequently used as water pipes and gas pipes. However, these metal tubes may corrode and lead to harmful substances such as lead, and in some cases, may corrode and cause a leakage accident. Therefore, in recent years, these pipes are being replaced by synthetic resin pipes such as polyethylene and polybden, which are excellent in corrosion resistance and chemical resistance.

  With the advent of this type of synthetic resin pipe, various pipe joints for connection have been developed.

  For example, as shown in FIG. 9, a heating wire 81 is embedded in a cylindrical joint 80 formed of a synthetic resin in advance, and a resin tube 84 is inserted between the stiffener 83 provided in a double tubular shape inside. In the inserted state, the heating wire 81 is energized from the terminal pin 82 protruding to the outside, the resin on the surface of the pipe is melted, the melted state is confirmed by the indicator 85, and the resin pipe 84 is integrated with the joint 80. there were.

In addition to this, a pipe joint is screwed into this female screw, and a cylindrical joint body provided with a female thread on the inner periphery and provided with a contact surface and a receiving surface on the inner back side of this female thread. A cylindrical pressing body provided with an external thread on the outer periphery, an annular lock ring (prevention ring) in which a plurality of restricting pieces protrude on one inner side, and a tubular core ring provided with a flange at the tip A synthetic resin pipe having a core ring inserted into the tip after the pressing body is screwed and integrated with the joint body so that the lock ring is fixedly positioned on the receiving surface in the joint body. In some cases, by inserting the inside of the pressing body, the restriction piece of the lock ring acts like a claw so as to prevent the synthetic resin tube from coming off. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 11-280981 (page 4, FIG. 2)

  In the above-described conventional pipe connection structure, those in which a seal tape is wound around the joint thread portion in advance or a sealing agent is applied have a problem that the work is troublesome and the construction work efficiency is poor.

  And if seal tape is used, if the winding around the threaded part is loose, the seal tape will not rotate with the male screw when screwing in. In order to prevent this, there is a problem that the thin and flexible sealing tape is broken and the work must be started again.

  In addition, when a sealant is used, this sealant is generally a liquid with a little viscosity and is adhesive and solidifies over time. If the sealing agent, which is a foreign material, flows into the pipe, an unexpected trouble such as clogging of the control valve may occur. On the other hand, if the amount of the sealing agent applied is small, sufficient sealing performance cannot be obtained and there is a risk of water leakage.

  In addition, those that connect pipes using joints with embedded heating wires have the problem that once the resin is melted and the resin pipes are joined, they cannot be removed and errors during construction are not allowed, Also, because the construction itself uses electricity, it is dangerous and power lines must be drawn to the construction site, which takes time and also requires time to heat and melt the resin, resulting in poor work efficiency. There was a problem. Furthermore, the buried heating wire is used only once, and wastes resources, and the one used in this way is difficult to reuse. It was.

  Further, in the case of using a lock ring disclosed in Japanese Patent Application Laid-Open No. 11-280981, when the pressing body is screwed and integrated into the joint body, if the tightening method is loose, the lock ring is not fixedly held. In addition, there is a possibility that the lock ring may not function sufficiently, and with use, the screw gradually loosens, and in the worst case, water leakage or gas leakage is assumed. In order to prevent this, if the pressing body is tightened strongly to the joint body, the screw thread may be crushed, and in this case, the same situation may be caused as a result. The work required skill.

  This invention makes it a subject to solve the problem which the said conventional piping connection structure had.

  In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention is provided with a male screw provided on an outer periphery of an attachment portion of an insertion body to which a tubular body is connected, on an inner periphery of a joint body. In the pipe connection structure in which the pipe body is communicated with the pipe line on the joint main body side by being screwed to the female thread formed, the pipe body is in contact with both between the joint main body and the mounting portion of the insertion body. A seal member for maintaining water tightness, a lock ring is provided on the inner periphery of the joint body so that the diameter of the lock ring can be increased, and a step in which the lock ring is fitted on the outer periphery of the mounting portion of the insert. Set up a section. Thus, the lock ring is fitted into the stepped portion at the screwing end position of the insert, so that the insert is positioned and connected to the joint body so as not to loosen. And

  The invention according to claim 2 adds a configuration in which an inclined guide surface is provided above the stepped portion of the mounting portion of the insertion body to the configuration of the invention according to claim 1, and when the insertion body is screwed into the joint body, The inclined guide surface is in sliding contact with a lock ring provided on the joint main body, and the diameter of the lock ring is expanded to guide the stepped portion.

  According to a third aspect of the present invention, a male screw provided on an outer periphery of an attachment portion of an insertion body to which a tubular body is connected is screwed to a female screw provided on an inner periphery of a joint body, whereby the tubular body is In the pipe connection structure that is connected to the pipe line on the joint body side, a seal member is provided between the joint body and the insertion body to maintain watertightness in contact with both, and the insertion body A lock ring is provided on the outer periphery of the attachment portion so that the diameter of the lock ring can be reduced, and a step portion to which the lock ring is fitted is provided on the inner periphery of the joint body. Thus, the lock ring is fitted into the stepped portion at the screwing end position of the insert, so that the insert is positioned and connected to the joint body so as not to loosen. And

  The invention according to claim 4 adds a configuration in which an inclined guide surface is provided below the stepped portion of the joint body to the configuration of the invention according to claim 3, and when the insertion body is screwed into the joint body, the inclined guide surface is It is characterized in that it is in sliding contact with a lock ring provided on the insert, and the lock ring is reduced in diameter and guided to the stepped portion.

  As described above, in the pipe connection structure according to claim 1 or 3 of the present invention, the lock ring is fitted into the stepped portion at the screwing end position of the insert, and the insert is the joint body. Since the seal member is interposed between the two, the work can be easily performed without using a tool such as a wrench. In addition, since the screwing end position of the insertion body can be recognized with a click feeling, there is no risk of over-screwing, and damage accidents caused by excessive force can be prevented, and even when multiple workers are working There is no unevenness in the mounting method, and there is an effect that the insertion body can be securely mounted at an accurate position in an airtight or watertight manner.

  In addition, since the insert is held by the lock ring so that it does not loosen, even if there is no risk of water leakage or gas leak, if the insert is rotated with a certain amount of force, it will lock. Since the ring can be disengaged, the construction is facilitated and the maintenance after the construction can be easily performed.

  Further, in the invention according to claim 2 or claim 4, since the inclined guide surface for guiding the lock ring is provided on the outer periphery of the mounting portion or the inner periphery of the joint, the feeding to the step portion of the lock ring is smooth, And it is made surely and there is an effect that workability is further improved.

  Hereinafter, the present invention will be described in detail based on illustrated embodiments.

  FIG. 1 is a cross-sectional view of a main part showing a pipe connection structure of the present invention, and FIG. 3 is a partially enlarged view thereof. In the figure, reference numeral 10 denotes a substantially cylindrical joint body having an internal thread 11 provided on the inner periphery, and this joint body 10 is connected to a fluid supply side pipe line such as a header side of a sprinkler digestion piping facility, for example. Yes.

  In addition, the insert 1 attached to the joint body 10 is formed in a stepped cylindrical shape having different upper and lower diameters from the middle, and a male screw 5 is provided on the outer periphery of the upper small diameter attachment portion 1. And two engagement grooves 8 and 9 for mounting the retaining ring 50 are provided on the inner periphery of the lower large-diameter pipe connection portion 2.

  The retaining ring 50 has a substantially annular shape as shown in FIG. 2, and a plurality of restricting pieces 51 protrude from the inner periphery of the retaining ring 51 while being inclined toward one side in the direction of the central axis. It is formed of a stainless steel plate having a thickness of 0.2 to 0.3 mm.

  In FIG. 1, reference numeral 60 indicates a tube body such as polybudene or polyethylene that is coupled and connected to the insert 1, and the outer diameter thereof is substantially equal to the inner diameter of the tube connection portion 3 of the insert 1. A sleeve 70 having a flange 71 at the tip is inserted into the tip (upper end in FIG. 1).

  Further, a concave groove 13 is provided on the inner periphery of the lower end of the joint body 10, and a lock ring 20 is fitted therein.

  As shown in FIG. 5, the lock ring 20 is substantially C-shaped in plan view with a part cut away, and is formed of spring steel so that the diameter can be expanded to some extent. The inner diameter of the lock ring 20 is set slightly smaller than the inner diameter of the lower end of the joint body 10. Therefore, in the state fitted in the concave groove 13, the inner end side thereof is held in a state protruding slightly inward from the inner peripheral surface of the joint 10 as shown in FIG. 3.

  Further, an engagement groove 12 is provided on the inner circumference on the upper side of the female screw 11 of the joint main body 10, and an O-ring 30 serving as a seal member is fitted therein.

  On the other hand, the insertion body 1 has an inclined guide surface in which the surface between the attachment portion 2 provided with the male screw 5 and the tube connection portion 3 continuous to the attachment portion 2 is expanded in diameter toward the tube connection portion 3 side. 6, a step portion 7 into which the lock ring 20 is fitted is provided below the inclined guide surface 6. Therefore, when the insertion body 1 is screwed and attached to the joint body 10, the stepped portion 7 faces the concave groove 13 provided in the joint body 10 at the screwing end position.

  Next, the procedure for connecting the pipes using the joint body 10 and the insert 1 will be described. First, the insert 1 is inserted into the interior of the joint body 10 from the lower open portion connected to a pipe line (not shown). Is inserted into the female screw 11 provided on the inner periphery of the joint 10, and the male screw 5 provided on the outer periphery of the fitting portion 1 is screwed into the female screw 11 provided on the outer periphery of the fitting 10. Screw in. At this time, there is no sealing tape or sealant that prevents the rotation of the screw part, and the screw itself is not formed into a tapered shape, so that the work can be performed without using a tool such as a wrench. Easy to do.

  When the insertion body 1 is screwed into the joint body 10 in this manner, the inclined guide surface 6 provided on the lower side of the male screw 5 is eventually held in the lock ring 20 held in the concave groove 13 of the joint body 10. As the insert 1 is screwed in, the lock ring 20 having springiness is slidably brought into contact with the inclined guide surface 6 to increase its diameter and is pushed into the concave groove 13.

  Then, when the insertion body 1 is further screwed from this state, the stepped portion 7 provided on the lower side of the inclined guide surface 6 eventually becomes a position facing the groove 13, so that it is located in the groove 13 here. The lock ring 20, which has been pushed out, is restored to its original state by its own elastic restoring force, and its inner end is fitted into the stepped portion 7. Therefore, the insertion body 1 that has been screwed stops at this position with a click feeling, and further screwing is prevented. At this time, the upper side of the mounting portion 2 is inserted inside the O-ring 30 held in the engagement groove 12 of the joint body 10, and the water-tightness between the joint body 10 and the insertion body 1 is secured by the O-ring 30. It is supposed to be blocked by.

  As described above, the insertion body 1 provided with the O-ring 40 and the retaining ring 50 on the inner periphery is attached to the joint body 10, and then the inner side of the pipe connection portion 3 of the insertion body 1 is attached to the distal end. When a tube 60 made of a synthetic resin such as polybutene or polyethylene into which the sleeve 70 is fitted is inserted, each regulating piece 51 of the retaining ring 50 provided on the inlet side (the lower side in FIG. 1) Since it is inclined in the insertion direction, the O-ring 40 provided on the back side (upper side in FIG. 1) is in contact with the surface of the tube body 60 and does not hinder its movement, and engages with the engagement groove 8. Therefore, it fits in the outside of the tube 60, and this also does not hinder its movement. Therefore, as shown in FIG. 1, the tube body 60 is pushed to a position where the tip of the sleeve 70 is in contact with the abutting portion 4 on the inner back side of the tube connecting portion 3 and is connected in a watertight state in this state. To do. The tubular body 60 inserted in this way is sealed watertight with an O-ring 40 in contact with the surface thereof, and the tip of the regulating piece 51 of the retaining ring 50 bites into the surface of the resin tubular body 60. Therefore, it is prevented from coming off.

  As described above, in the pipe connection structure of the present invention, the tubular body 60 can be easily obtained simply by screwing the insertion body 1 into the joint body 10 and inserting the tubular body 60 into which the sleeve 70 is fitted. Can be connected so as not to leak water. Therefore, it is not necessary to take waterproof means such as winding a sealing tape or applying a sealing agent during the work, and the work itself can be easily performed without using a tool such as a wrench. Since the screwing end position can be recognized with a click feeling, there is no possibility of excessive screwing, and there is no possibility of uneven construction due to differences in operators.

  Further, in the connection structure of the present invention, the lock ring 20 has the curved arcuate portion 20a on the inside thereof engaged with the step portion 7 as shown in FIG. When rotated, the upper corner portion 7a of the step portion 7 comes into pressure contact with the curved portion and acts to expand the lock ring 20 outward. Therefore, although a little larger force is required than when attaching, the insertion body 1 can be removed from the joint body 10 and there is no possibility of damaging the lock ring 20. Thus, the insert 1 can be attached again. The restricting piece 51 of the retaining ring 50 provided in the insertion body 1 only restricts the movement in the direction in which the tubular body 60 is pulled out, and does not hinder the movement of rotating the tubular body 60. Therefore, the insertion body 1 can be detached from the joint body 10 even after the pipe body 60 is connected.

  FIG. 6 shows another embodiment of the lock ring. As shown in the figure, in this case, the lock ring 21 does not have an arc shape with a constant inner diameter, and is bent at a predetermined position so that the three locking portions 21a protrude inward. Is. The lock ring 21 is also configured to be spread outwardly in contact with the inclined guide surface 6 when the insert 1 is screwed into the joint 10 in the same manner as described above, and the step 7 is provided. When the locking portion 21a is fitted into the stepped portion 7, the inserted body 1 functions to be positioned and held in a state where it is connected to the joint 10.

  FIG. 7 is a cross-sectional view showing an engaged state of the lock ring 21. As shown in the figure, the lock ring 21 is not formed of a wire having a round cross section, but is formed of a member having an approximately pentagonal cross section having an inner peripheral side (right side in FIG. 7). Therefore, in this case, when the insertion body 1 is rotated so as to be removed from the joint 10, the upper corner portion 7 a of the step portion 7 is in contact with the inclined surface on the inner peripheral upper side of the lock ring 21, and the lock ring 21 is moved outside. The left side in FIG. 7 acts so as to be expanded, whereby the lock ring 21 and the stepped portion 7 are disengaged, and the insert 1 is removed from the joint 10.

  FIG. 8 is a cross-sectional view showing another example of the insert 1 used in the present invention. As shown in the drawing, in this case, a concave groove 19 for holding the lock ring 22 is provided on the outer periphery of the mounting portion 2 of the insertion body 1, and a step portion 14 with which the lock ring 22 engages is provided on the inner periphery of the joint body 10. Provided. Therefore, the lock ring 22 is slidably brought into contact with the inclined guide surface 15 provided on the inner periphery of the joint body 10 when the insert 1 is attached, and is pressed inward so as to reduce the diameter. At the position where the step 14 is provided, it opens outward and fits into the step 14. At this time, the O-ring 30 held in the engaging groove 18 formed on the upper side of the concave groove 19 is in contact with the inner peripheral surface of the joint body 10 and is watertightly sealed between the two. Exactly the same as above. Therefore, the function is not different from that of the above embodiment.

In this embodiment, when the insertion body 1 is rotated in the direction to remove, the lower corner portion 14a of the step portion 14 formed on the joint body 10 becomes a curved surface outside the lock ring 22. Since the lock ring 22 is pressed, the lock ring 22 receives a force in the direction of reducing the diameter, and is disengaged from the stepped portion 14. As described above, in the pipe connection structure of the present invention, the insert 1 is It can be easily attached to the joint body 10 so as to be detachable, and can be reliably attached to an accurate position so that no one leaks water.

  In the illustrated embodiment, the lock rings 20 and 21 are illustrated with a part of the periphery cut away. However, in the lock ring used in the connection structure of the present invention, the engaging portion has a reduced diameter or What is necessary is just to have a spring property in the direction which expands, and can be pushed, for example, the cyclic | annular thing which continued the some latching | locking part in the polygonal shape may be sufficient.

  Further, in the embodiment, the insertion body into which the resin pipe body is inserted and connected is illustrated, but this insertion body is connected to the pipe body so as not to prevent the screw connection with the joint body. For example, the pipe body may be attached in a rotatable manner in advance. Therefore, in this case, the tube body is not limited to the resin tube but may be a metal tube.

It is sectional drawing of the principal part which showed the piping connection structure of this invention. It is a side view of a retaining ring. It is a principal part enlarged view of FIG. It is a principal part cross-sectional view of the coupling shown in FIG. It is a top view of a lock ring. It is a cross-sectional view of the attachment state which showed the other example of the lock ring. It is principal part sectional drawing which showed the engagement state by the other lock ring. It is the principal part notch side view which showed other embodiment of this invention. It is a principal part notch perspective view of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insert body 2 Attachment part 3 Pipe connection part 4 Contact part 5 Male screw 6,15 Inclination guide surface 7,14 Step part 7a, 14a Corner | gear part 8,9,12,18 Engagement groove | channel 13,19 Recessed groove | channel 10 Joint Main body 11 Female screw 20, 21, 22 Lock ring 20a Arc-shaped portion 21a Engagement portion 30, 40 O-ring (seal member)
50 retaining ring 51 restricting piece 60 tubular body 70 sleeve 71 flange

Claims (4)

The pipe is connected to the pipe line on the joint body side by screwing the male screw provided on the outer periphery of the attachment portion of the insertion body to which the pipe body is connected to the female screw provided on the inner circumference of the joint body. In the pipe connection structure
Between the joint body and the mounting portion of the insert, a seal member is provided for maintaining water tightness in contact with both, and a lock ring is provided on the inner periphery of the joint body so that the diameter of the lock ring can be expanded, and On the outer periphery of the mounting portion of the insert, a step portion to which the lock ring is fitted is provided. When the lock ring is fitted into the step portion at the screwing end position of the insert, the insert is A pipe connection structure characterized by being positioned and coupled to a joint body so as not to loosen. An inclined guide surface is provided above the stepped portion of the mounting portion of the insertion body. When the insertion body is screwed into the joint body, the inclined guide surface comes into sliding contact with a lock ring provided on the joint body, and the lock ring is expanded. The pipe connection structure according to claim 1, wherein the pipe connection structure is formed so as to be guided to a stepped portion. The pipe is connected to the pipe line on the joint body side by screwing the male screw provided on the outer periphery of the attachment portion of the insertion body to which the pipe body is connected to the female screw provided on the inner circumference of the joint body. In the pipe connection structure
Between the joint body and the insertion body, a seal member is provided for contacting and maintaining watertightness, and a lock ring is provided on the outer periphery of the attachment portion of the insertion body so that the diameter can be reduced, and On the inner periphery of the joint body, a step portion to which the lock ring is fitted is provided, and the insert is positioned by fitting the lock ring into the step portion at the screwing end position of the insert, A pipe connection structure characterized by being connected to the joint body so as not to loosen. An inclined guide surface is provided below the stepped portion of the joint body. When the insert is screwed into the joint body, the inclined guide surface comes into sliding contact with the lock ring provided on the insert body, and the diameter of the lock ring is reduced to reduce the step. The pipe connection structure according to claim 3, wherein the pipe connection structure is guided to a section.

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