JP2008020076A - Pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe joint which can follow twist of a pipe with enabling a lock ring to rotate together with an inserted pipe and into which an insertion pipe can be easily inserted by a single operation while the inserted pipe reliably exerts a draw-out preventing force and is connected in an extremely stable state, preventing the leak of water. <P>SOLUTION: A joint body 10 is constituted of a cylindrical joint member 11 and a lid member 12. Seal rings 17, 18 and lock rings for preventing the fall of an inserted pipe are placed inside the joint body 10. The lock rings 15, 16 are arranged to enable the same to rotate together with the joint body 10. A ring part 19 of the lock ring is inclined by 3-7° in relation to a perpendicular direction of a center axis of the joint body 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pipe joint that can connect resin pipes widely used in water supply, hot water supply, air conditioning systems, fire extinguishing equipment, and the like with one touch.

  This resin pipe is widely applied to water supply, hot water supply or air conditioning piping in buildings, floor heating of detached houses, etc. And the pipe joint for connecting this resin pipe is connected to the pipe. While it is simple, it is essential that the pipe retaining function is reliable and there is no worry of water leakage.

  Conventionally, as shown in FIG. 12 (a), a spacer 4 having a thickness of 0.3 to 1.0 mm is interposed between a pair of lock rings 3a and 3b which are positioned and fixed by screwing a pressing body 2 into a joint body 1. There is a joint that is interposed to prevent the resin pipe 5 from coming off (see, for example, Patent Document 1).

  On the other hand, there is one in which protrusions are provided in the vicinity of the tips of a plurality of claws facing the front side of the pipe insertion direction (for example, see Patent Document 2). In addition, there is one in which a notch portion is formed at both ends of the restriction piece provided on the lock ring so as to correspond to the depth of biting into the pipe (for example, refer to Patent Document 3), and an inner edge that bites into the pipe; There is a lock ring that is chamfered at a portion that restricts biting (see, for example, Patent Document 4).

Japanese Patent No. 3165109 Japanese Patent No. 2685105 Japanese Patent No. 2945653 Japanese Patent No. 2920146

  However, in the invention described in Patent Document 1, the pair of lock rings 3a and 3b are positioned and fixed on the receiving surface 1a in the joint body 1 by the tip of the pressing body 2 so as to be immovable in the axial direction and the circumferential direction. Therefore, as shown in FIGS. 13A and 13B, when the pipe 5 is inserted, only the claws 6a and 6b of the lock rings 3a and 3b are deformed, so that the pipe resists the elastic force of the claws. It was difficult to insert the pipe because the insertion force was increased. In addition, when the inserted pipe 5 rotates, the outer periphery of the pipe 5 may be damaged in the circumferential direction, and the pipe 5 may be cut from that portion.

  In particular, since the resin pipe 5 is affected by elongation, the deformation method differs between the lock ring 3b on the pipe insertion port side and the lock ring 3a on the back side, and as shown in FIG. Since the extension of the pipe 5 is larger on the side, the deformation amount of the lock ring 3b following the extension inevitably increases. As a result, as shown in FIG. 12C, the amount of biting into the pipe 5 of the lock ring 3b on the insertion port side is always excessive, and the pipe 5 may be cut from that portion. In this case, if the number of lock rings is increased, the amount of individual deformation is reduced, and even if this point is eliminated, the pipe insertion becomes extremely difficult.

  The inventions described in Patent Document 2 and Patent Document 3 both attempt to limit the biting into the pipe by the shape of the lock ring, but in reality, a metal thin plate-shaped lock ring is soft. The effect of preventing the resin pipe from biting in varies, and the restricted part bites in, so that the pipe may be cut as a result. Of these, in the invention of Patent Document 3, the slits are formed between the claws so as to allow the claws to spread when the pipes are inserted, and the pipes are inserted smoothly. In some cases, the slit alone is not sufficient, and in some cases, the pipe has to be inserted into the joint with a strong force in order to forcibly expand the claws.

  Furthermore, in the invention described in Patent Document 4, chamfering to the inner end edge that bites into the resin pipe is effective against scratches at the time of pipe insertion, but chamfering to a part that restricts biting is also possible. As in the above example, the effect varies, and as a result, the resin pipe may be cut and the pipe may be cut.

  The present invention was developed to solve the problems of conventional one-touch fittings, and the object of the present invention is to allow the lock ring and the inserted pipe to rotate together to follow the twisting of the pipe. In addition, the insertion pipe can be easily inserted with a single touch. On the other hand, the inserted pipe is reliably connected with an excellent pull-out preventing force, and there is no risk of water leakage. It is to provide a pipe joint.

  In order to achieve the above object, the invention according to claim 1 is configured such that a joint body is constituted by a cylindrical joint member and a lid member, and a seal ring and a lock ring for preventing insertion pipes are mounted in the joint body. This is a pipe joint in which this lock ring is arranged so as to be able to rotate together with the insertion pipe.

  The invention according to claim 2 is a pipe joint in which the ring portion of the lock ring is inclined by 3 to 7 degrees with respect to the direction orthogonal to the central axis of the joint body, and the invention according to claim 3 is provided in the ring portion of the lock ring. This is a pipe joint in which holding claws are formed so as to protrude in an inclined manner on the circumference, and a separation part is provided between the ring part of this lock ring and the mounting part in the joint body.

The invention according to claim 4, the ring portion of the lock ring with tilting 3-7 degrees with respect to the direction perpendicular to the central axis of the joint body, the holding claws projecting form the inclined shape to the inner periphery of the ring portion to the ring portion In this pipe joint, the pipe can be easily inserted and the pipe pull-out preventing force can be obtained by further inclining the pipe.

  As apparent from the above, according to the invention of claim 1, the seal ring and the lock ring for preventing the insertion pipe from coming off are mounted in the joint body, and the lock ring is provided so as to be able to rotate together with the insertion pipe. Therefore, it is possible to reliably follow the twisting of the insertion pipe, and the inserted pipe is reliably connected in a very stable state with its pull-out prevention force reliably, and there is no fear of water leakage. Obtainable.

  According to the second aspect of the present invention, the lock ring and the insertion pipe can be easily rotated to further prevent twisting of the pipe, and the pipe can be securely held even when the holding claw is not provided, and the pipe may be cut. There is no.

  According to the invention of claim 3, since the lock ring is provided with a holding claw protrudingly formed on the inner periphery of the ring portion, and a separation portion is provided between the mounting surface of the joint body facing the ring portion and the ring portion. The lock ring can be rotated to reliably follow the twist of the insertion pipe, and the pipe can be easily inserted into the pipe joint, while the inserted pipe is reliably prevented from being pulled out and stable. Connection status is maintained.

  According to the invention of claim 4, the pipe can be easily inserted into the pipe joint, and when the pipe is pulled out, the entire lock ring is raised by the inclination angle of the seat surface, and the holding claw of the lock ring is bent by the bending angle. Therefore, the pipe can be reliably held without breaking.

  An example of embodiment at the time of connecting a resin pipe to a pipe joint in the present invention is explained in full detail based on a drawing.

  FIG. 1 is a perspective view showing an example of a pipe joint according to the present invention, FIG. 2 is an exploded perspective view of the same, and FIG. 3 is a partial sectional view showing a state in which a resin pipe is connected to the pipe joint. In the figure, reference numeral 10 denotes a joint body made of metal such as brass or bronze. The joint body 10 in this example is a male screw 11 a of a tubular joint member 11 and a female of a tubular lid member (nut or cap) 12. A screw 12a is screwed together, and an end portion of the joint member 11 is provided with a male screw portion 11b (or a female screw or other connecting portion) that is connected to a header, a connecting member, or a pipe (not shown). ing. The lid member 12 is not limited to the cap structure described above and may be a bush having a male screw. In this case, the bush is screwed into the joint member to constitute the joint body. A confirmation window 27 is formed on the outer peripheral surface of the lid member 12.

  The resin pipe 13 for connecting to the joint body 10 is a pipe formed of a resin material such as cross-linked polyethylene or polybutene. When the pipe 13 is connected to the joint body 10, the resin pipe 13 is connected to the tip insertion portion of the resin pipe 13. A metal core ring 14 such as bronze is fitted to maintain the amount of biting of the lock rings 15 and 16 described later and the sealing performance of the seal ring 17 or 18. A flange 14a is formed at the tip of the core ring 14, and a tapered surface 14b is formed so as to protect the end of the resin pipe 13 and smoothly insert the pipe 13 into the joint body 1. Yes. The pipe 13 may be made of copper in addition to resin.

  In FIG. 2, the lock rings 15 and 16 formed of stainless steel or the like are such that the ring portion 19 is inclined by 3 to 5 degrees with respect to the direction orthogonal to the central axis of the joint body. In this example, the lock rings 15 and 16 are shown in FIG. Thus, it is bent so as to incline toward the annular spacer 26 side by about 5 degrees. By inclining the ring portion 19, the contact area with parts such as the joint body 10 that comes into contact with the ring portion 19 is reduced, and the frictional resistance is reduced, so that the lock rings 15 and 16 are easily rotated. Therefore, in the joint body 10 constituted by the joint member 11 and the lid member 12, the insertion pipe 13 and the lock rings 15 and 16 are provided so as to be able to rotate together.

  When the angle of inclination of the ring portion is smaller than 3 degrees, when fluid pressure is applied to the pipe 13 connected to the joint body 10, a pulling force is applied to the pipe 13, and the force causes the lock rings 15 and 16 to move. Since the ring portion 19 is pressed against the parts such as the joint body 10 and the contact area with the parts such as the joint body 10 is increased and the frictional resistance is increased, the lock rings 15 and 16 are difficult to rotate. On the other hand, when the angle is greater than 7 degrees, the angle at which a holding claw 20 to be described later contacts the pipe 13 becomes shallow, and when a pulling force is applied to the pipe 13, there is a possibility that the pipe 13 cannot be reliably held. If the holding claws 20 are lengthened in order to solve this problem, the depth of biting into the pipe 13 when standing is increased, and the pipe 13 may be easily cut. Therefore, the inclination angle of the ring portion may be in the range of 3 to 7 degrees, but 5 to 7 degrees is more desirable as described above in order to reliably obtain the rotation of the lock rings 15 and 16.

  As shown in FIG. 7, the holding claw 20 protrudes from the inner periphery of the ring portion 19 with a predetermined inclination angle (the initial bending angle of the lock ring in this example is 45 degrees) from the ring portion 19. So that the pipe can be easily inserted, and a pipe pull-out prevention force is obtained. When the pipe is pulled out, the holding claws 20 bite into the outer peripheral surface of the pipe 13 to restrict the pipe from being pulled out. ing. As shown in FIG. 5, each holding claw 20 is formed with a slit 20a and a concave portion 20b at the center position. By forming this concave portion 20b, even if the holding claw 20 stands up, the entire holding claw 20 bites into the pipe. So that there is no. Further, by forming the recess 20b, the pipe biting portion 20c is formed at two locations along both sides of the holding claw 20. As described above, the lock rings 15 and 16 in this example do not have a portion to restrict the biting into the pipe 13 due to the shape of the lock ring.

The biting portions 20c may be provided at three or more positions at the tip of each holding claw 20. When the biting portions 20c are provided at a plurality of locations as described above, the biting portions 20c are formed narrowly, so that the holding claw The contact pressure between the pipe 20 and the pipe 13 becomes high, and it is easy to bite into a relatively soft pipe 13 such as a polybutene pipe as well as a relatively hard pipe such as a polyethylene pipe. Moreover, since the point at the time of the holding claw 20 holding the pipe 13 increases, the pipe 13 can be held reliably.
If the tip of the biting portion 20c has a small radius, the outer periphery of the pipe 13 is not damaged when the pipe 13 is inserted into the joint body 10.

When the pipe 13 is inserted, each holding claw 20 is expanded by the slit 20a as the pipe 13 is inserted, and the inclination angle becomes large. In combination with the inclination of the ring portion 19 and the separation portion 24 described later, the inclination angle of the lock ring with respect to the pipe Is further increased, and the pipe 13 can be smoothly inserted into the joint body 10.
On the other hand, when a pulling force is applied to the pipe 13 after the pipe is inserted, the holding claws 20 are slightly spread during lock ring molding as will be described later. In the process of shallowing, the side portions 20d of the adjacent holding claws 20 come into contact with each other. Even if the holding claws 20 are to rise further due to the pulling force of the pipe 13, the slits 20 a between the two holding claws 20 are narrowed, so that the holding claws 20 are regulated to each other and the standing is suppressed. Therefore, the holding claw 20 can hold the pipe without the two biting portions 20c and 20c being substantially integrated and causing a sudden decrease in the contact angle with the pipe 13. Thus, in the standing process of each holding claw 20, side portions 20d of each holding claw 20 are brought into contact with each other, and a pipe joint having sufficient pipe holding force is obtained by holding the inclination angle of the holding claw 20. I did it.
In addition, since the side part 20d can be secured long by sharing the side part 20d of the holding claw 20 and the side part of the biting part 20c, the side part 20d and the biting part 20c can be accurately used when forming the lock ring. It can be formed well.

More preferably, the side portion 20d is configured so that when the pulling force is applied to the pipe 13, the holding claws 20 stand up and the pipe biting portion 20c bites into the pipe 13 so that the holding claws 20 come into contact with each other. It is preferable to form toward the ring part 19 from the position slightly from a ring part from the pipe biting part 20c front-end | tip of the holding nail | claw 20, as shown in FIG.
Further, by forming the biting portion 20c on both sides of the holding claw 20, the area of the side portion 20d of the holding claw 20 is increased, so that the ratio of the holding claw is increased during the drawing bending process, and as a result, the slit 20a is formed. It can be formed narrower.

  In FIG. 5, when the holding claws 20 of the lock rings 15 and 16 are erected in the same horizontal direction as the ring portion 19, the amount of pipe biting of the holding claws 20 is 35 to 50% of the thickness cross-sectional area of the pipe 13. Therefore, even when an excessive pipe pulling force is applied, the pipe 13 is hardly broken.

  Here, the case where a lock ring is shape | molded is demonstrated. FIG. 8A shows a state in which the lock ring is formed into a flat shape. Moreover, in FIG.8 (b), it is the state which bent the holding nail | claw by the bending process. The solid line portion shows the shape when the holding claw is bent by drawing bending, and the holding claw is slightly expanded by this drawing bending, and is formed at an inclination of about 45 degrees. Specifically, the holding claws are stretched by applying a squeezing using a press machine, resulting in a shape that expands in the circumferential direction, and accordingly, the slit width becomes slightly narrow. Therefore, when a pulling force is applied to the pipe 13, the slit width becomes zero as shown in FIG. 8C before the holding claws 20 stand up completely, and the respective holding claw side surfaces 20d come into contact with each other. Even if the holding claws 20 try to stand up further from this state, the holding claws 20 interfere with each other to prevent the standing up, so that the bending angle is maintained and the pipe 13 can be prevented from coming off. The angle α at this time is preferably processed so as to be held at 10 to 20 degrees, but more preferably, it is processed so as to be held at 12 to 20 degrees.

  The broken line portion in FIG. 8B shows the shape when the holding claw is simply bent by a normal bending process. In this case, the slit width is widened by bending of the holding claw, When the holding claw is raised by applying a pulling force, the slit width is lost when the holding claw is completely raised and the bending angle of the holding claw is lost, which is not desirable. In FIGS. 8A, 8B, and 8C, cross-sectional views taken along lines BB, CC, and DD are shown on the left side, respectively.

By using the lock rings 15 and 16, the pipe 13 can be held regardless of whether it is a polyethylene pipe or a polybutene pipe. In general, polyethylene pipes are relatively hard and metal lock ring claws are easy to bite, while polybutene pipes are relatively soft and elastic, and nails with low contact surface pressure with the pipe escape from the outer surface of the pipe. However, the contact surface pressure of the claw against the tube is low, as in the case of a lock ring with a circular arc-shaped projection with a large radius at the center of the tip of each claw shown in the prior art. There is no risk that the pipe will be insufficiently bited or the pipe will be pulled out of the joint when a pulling force is applied to the pipe.
In this way, it is not necessary to provide a separate lock ring exclusively for polybutene pipes, and it is a lock ring that can be shared with polyethylene pipes and polybutene pipes, which increases the number of parts and management man-hours and increases costs. There is no. Moreover, there is no possibility that a lock ring for different types of pipes will be mistakenly assembled when the pipe joint body is assembled.

  The plurality of lock rings 15 and 16 (two in this example) are mounted on the mounting portion 22 in the joint body with a spacer ring 21 formed of metal, resin or the like interposed between the ring portions 19. . In this example, the thickness of the spacer ring 21 is preferably 0.7 to 1.5 mm. When the thickness of the spacer ring 21 is 0.5 mm or less, the lock rings 15 and 16 behave substantially the same, and all the claws Is not desirable because it stands up at once and the pipe breaks. In Examples described later, by combining with the angle restricting portion 28, a preferable result was obtained when the spacer ring thickness 21 was 1.0 to 1.5 mm.

  The mounting portion 22 in this example is a transparent or translucent shape having a pressure strength, cold resistance, hydrolysis resistance, and chlorine resistance fitted to the lid member 12 with a step portion 12b provided on the inner peripheral side of the lid member 12. Between the annular spacer 26 provided at the end of the see-through cylinder 25. A separation portion 24 is provided between at least the attachment surface 23 of the attachment portion 22 and the ring portion 19. In FIG. 6A, the separation distance between the lock ring 15 and the step portion 12 b in the joint body axial direction of the attachment portion 22. A is 0.1 to 0.8 mm. As a result, the lock ring 15 can be inclined by the distance A, and the pipe can be inserted smoothly. Further, due to the separation distance A, the lock rings 15 and 16 can rotate within the joint body. Therefore, in the joint body 10 constituted by the joint member 11 and the lid member 12, the insertion pipe 13 and the lock rings 15 and 16 are provided so as to be able to rotate together. If the separation distance A is greater than 0.8 mm, when a pulling force is applied to the pipe 13, the outer peripheral side of the ring portion 19 is inclined in the direction of the joint member 11, and the holding claws 20 are attached to the pipe 13. Since the contact angle becomes shallow, there is a possibility that sufficient holding of the pipe cannot be performed.

  In addition, it is also possible to prevent the co-rotation of the pipe 13 by inclining only the ring portion 19 of the lock ring without providing the separation portion 24. In this case, by inclining the ring portion 19 at an appropriate angle, Since the contact area with the parts such as the joint body 10 to be contacted is reduced and the frictional resistance is reduced, the lock ring is easily rotated.

  The angle restricting portion 28 is provided integrally with the joint body 10 or separately, and restricts the deformation angle of the lock ring 15. In this example, in FIG. 4, the angle restricting portion 28 provided integrally with the lid member 12 is provided integrally. The angle restricting portion 28 may be provided integrally or separately in the joint body 10 and is not limited to the above example. When the pulling force is applied to the pipe 13, the inclination angle of the angle restricting portion 28 is such that the deformation amount of the lock ring 15 attached to the pipe insertion port side is less than the deformation amount of the lock ring 16 on the back side. The inclination angle of the holding claw 20 of the lock ring 15 is set to be equal to or less than the inclination angle so that the two lock rings do not come into contact with each other. In this example, the angle restricting portion 28 is arbitrarily set in accordance with the nominal diameter of the joint, etc. within an angle range of greater than 0 degree and less than 40 degrees with respect to the initial bending angle of 45 degrees of the holding claw 20 of the lock ring 15. Is set. Further, the angle restricting portion 28 can hold the pipe by the lock ring without breaking the pipe by reducing the angle as the nominal diameter of the joint increases.

The see-through cylinder 25 is disposed between the outer peripheral surface of the pipe 13 and the inner peripheral surface of the joint main body 10, but the end of the female screw 12 a of the lid member 12 constituting the joint main body 10, and the joint main body 10. The male screw base is brought into contact so that the lid member 12 cannot be screwed more than necessary so that the fastening force by the lid member 12 is not applied to the see-through tube 25.
The lid member 12 is provided with a stepped portion 12c, and an annular spacer 26 is engaged therewith, so that the lock ring mounting portion is reliably secured.

Next, the operation in the above embodiment will be described.
2 and 3, when the seal ring 18 is attached to the corner portion of the engaging surface 11 c of the joint member 11 and the fluoroscopic cylinder 25 is inserted into the joint member 11, the engaging portion 25 a of the fluoroscopic cylinder 25 becomes the joint member 11. The seal ring 18 is mounted on the mounting step 25b, and the see-through tube 25 and the joint member 11 at the liquid contact portion are hermetically sealed.
Next, the seal ring 17 is attached to the attachment portion 25 c formed at the rear end portion of the see-through cylinder 25.

  On the other hand, two lock rings 15 and 16 are mounted on the mounting portion 22 of the lid member 12 via the spacer ring 21, and an annular spacer 26 is interposed between the lock ring 16 and the seal ring 17. The joint body 10 is configured by inserting the female thread 12 a of the lid member 12 into the male thread 11 a of the joint member 11.

  When the resin pipe 13 is connected to the joint body 10, the core ring 14 is fitted from the tip of the pipe 13, and the flange portion 14 a of the core ring 14 is fitted to the end face of the pipe 13. When the resin pipe 13 is inserted from the pipe insertion port 29 of the lid member 12, in the initial state shown in FIG. 6A, the lock ring 15 is separated from the stepped portion 12b by a distance A and the ring portion. 19 is disposed in an inclined state at an angle of about 5 degrees, and the holding claw 20 of the lock ring 15 has an angle of about 45 degrees with respect to the ring portion 19, so that the holding claw 20 is in total It touches the outer circumference of the pipe at an angle of about 50 degrees. This structure is the same for the lock ring 16. Next, as shown in FIG. 5B, the lock ring 15 is further inclined within the range of the distance A. In FIG. 5C, the pipe is easily inserted while the lock ring 16 is also tilted. Since the lock rings 15 and 16 have the same angle because they are easily inserted in this way, the pipes can be easily inserted without overlapping. In this case, the lock rings 15 and 16 are rotatable in the circumferential direction, and are provided so as to be able to follow pipe twisting and the like.

  Since the bearing surface of the ring portion 19 of the lock rings 15 and 16 has an inclination angle of 3 to 7 degrees, the contact area is reduced, and the pipe 13 is placed in a state where the pipe 13 and the lock rings 15 and 16 are likely to rotate together. It can be held firmly. Furthermore, even when there is no separation distance A, the ring portion 19 has a reduced contact portion between the step portion 12b and the spacer ring 21, and the lock rings 15 and 16 can be rotated to follow the twisting of the pipe. Furthermore, by providing the separation distance A as described above, the lock ring 15 can be rotated more easily, and a function of increasing the inclination and facilitating pipe insertion can be exhibited.

Next, as shown in FIG. 3, when the pipe 13 is inserted until it comes into contact with the pipe contact surface 25 d provided on the inner peripheral surface of the see-through cylinder 25, the lock rings 15 and 16 bite into the outer peripheral surface of the pipe 13 to prevent the pipe 13 from coming off. At the same time, the outer peripheral surface of the pipe 13 and the inner peripheral surface of the see-through cylinder 25 are securely sealed by the seal ring 17.
At this time, the holding claws 20 of the lock rings 15 and 16 have a recess 20b deeply formed at the center thereof, so that they bite into the pipe 13 from the biting portions 20c at both ends.

  In a pipe joint using a lock ring, the area where the biting portion bites into the pipe gradually increases as the pulling force is applied to the pipe and the holding claws stand up. In this example, the biting portion 20c has a constant thickness. By forming a trapezoidal shape with a plate shape and a shallow angle, the amount of increase in biting can be suppressed, and the contact surface pressure between the holding claw 20 and the pipe 13 can be kept high, and the biting into the pipe 13 is easy. can do. Therefore, the phenomenon that the biting area increases rapidly, the contact surface pressure with the pipe 13 decreases as the holding claw 20 rises, and the biting becomes difficult to be suppressed.

  In this example, the pipe insertion port 29 of the lid member 12 is not provided with a seal member for sealing and sealing between the lid member 12 and the outer periphery of the pipe 13, that is, when the pipe 13 is inserted into the joint body 10. First, the structure contacts the lock ring 15. Therefore, the pipe insertion operator can confirm whether or not the pipe 13 has been inserted until the pipe 13 reaches the lock ring 15 with this contact feeling, and there is no misperception compared to a joint having a structure that first contacts the seal member when the pipe is inserted. Reliable pipe insertion can be performed.

  The resin pipe 13 inserted into the joint body 10 can be visually observed from the outside through a transparent or translucent see-through tube 25 from a confirmation window 27 formed on the outer peripheral surface of the lid member 12 of the joint body 10. After the confirmation of the mounting of the resin pipe 13 to the joint body 10 by the confirmation window 27, when a fluid such as cold water or hot water is passed through the pipe 13, the fluid is separated from the see-through cylinder 25, the outer periphery of the pipe 13, and the see-through cylinder 25. Although they enter the gaps of the joint member 11, both are sealed by the seal rings 17 and 18, so that no fluid leaks from the confirmation window 27 provided in the lid member 12 to the outside of the pipe joint.

  As shown in FIG. 4A, when a pulling force is applied to the pipe 13 in the direction of the arrow, the lock rings 15 and 16 are drawn toward the stepped portion 12b and the ring portion 19 becomes vertical, and the distance A in FIG. The holding claw 20 comes into contact with the outer periphery of the pipe at an angle of about 45 degrees. Next, in FIG. 4B, the holding claws 20 of the lock rings 15 and 16 that prevent the pipe 13 from coming off gradually rise, and eventually the holding claws 20 of the lock ring 15 stand up most. Even in this case, the amount of biting of the holding claws 20 into the pipe 13 is 35 to 50% of the wall cross-sectional area of the pipe 13, and the pipe 13 is secured with more than half the wall thickness. There is no fear of being done. At this time, the recessed portion 20b of the holding claw 20 is formed deeply so as not to bite into the pipe 13 at all, and the entire holding claw 20 is prevented from biting into the pipe 13, so that the initial thickness of the pipe 13 is partially increased. The breakage of the pipe 13 can be further suppressed.

In the standing process of the holding claws 20, the side portions 20d of the holding claws 20 are in contact with each other, and by using the lock rings 15 and 16 that regulate the standing of each other, the holding claws 20 are tilted in a state in which the standing claws 20 are prevented from standing up. The angle can be maintained, the holding claws 20 can be prevented from standing further, the holding force of the pipe 13 can be maintained, and the pipe can be reliably prevented from breaking.
Further, since the pipe biting portions 20c are formed on both sides of the holding claw 20, it is possible to immediately follow the narrowing of the slit 20a and to suppress the standing claw 20 from standing up early. Complete standing can be further prevented. Further, the area of the side portion 20d can be increased, and the slit 20a can be formed narrower by increasing the area by drawing and bending, and the contact of the side portion 20d when the holding claw 20 rises can be achieved. This can be done reliably from the beginning.

  Note that, as in the present embodiment, the pipe biting portion 20c in each holding claw 20 is formed thinly along the side portion 20d, thereby ensuring the biting property to the pipe 13 and the slit 20a by the contact of the holding claw 20. The pipe biting portions 20c adjacent to each other can be integrated to hold the pipe 13, and the holding force of the pipe can be sufficiently secured. Further, since the holding claw 20 of the lock ring comes into contact with the angle restricting portion 28 provided integrally with or separately from the inside of the joint main body 10, the force of preventing the holding claw 20 from biting into the pipe 13 is increased, and the pipe 13 is securely attached. Breakage can be prevented.

  Since the lock rings 15 and 16 can rotate together with the pipe 13, as shown in FIG. 11 (a), there is no problem with the lock ring in the normal state. As shown in FIG. 4, when the pipe is bent, the lock ring undergoes partial deformation, and the force applied to the lock ring varies depending on the position. However, according to this example, since the angle restricting portion 28 is provided, the lock rings 15 and 16 are not locally changed as shown in FIG.

Since the lock ring 15 on the front side reliably receives a part of the pulling force of the pipe 13, the force applied to the lock ring 16 in the back can be reduced, the deformation amount of the holding claw 20 can be suppressed, and the bite into the pipe 13 can be suppressed. The angle is shallow, the spring force is maintained, and the force for gripping the pipe 13 is increased.
Further, since the movement amount of the pipe 13 is also suppressed, there is no influence on the sealing performance with the seal ring 17 or the like.

An example of implementation of the pipe joint in the present invention will be specifically described.
The joint size in this example is 13A, and the initial bending angle of the holding claw of the lock ring is 45 degrees.

  The graph shown in FIG. 9 is an example showing the relationship between the pipe stroke and the tensile force in the cross-linked polyethylene pipe (PEX pipe), and the graph shown in FIG. 10 is the pipe in the polybutene pipe (PB pipe). This is an example showing the relationship between the stroke and the tensile force. In both figures, the solid line shows that when the pipe pulling force is applied, the pipe is stretched and there is no breakage of the pipe at the lock ring bite portion, which is indicated by a double circle. The broken line indicates that the pipe stretches when the pipe pulling force is applied, but the pipe breaks at the lock ring bite portion, and this is indicated by a circle. The chain line indicates that the pipe did not stretch when the pipe pull-out force was applied, but had the strength to reach the yield point of the pipe material, and also indicated that the pipe broke at the lock ring bite portion, which was indicated by a triangle. . In addition, the case where the pipe broke at the rock ring biting portion without reaching the yield point of the pipe material is indicated by x in the table.

  In Table 1, the joint size is 13A (the cross-sectional area of the pipe 13A is approximately 98 square millimeters), and the initial bending angle of the holding claw of the lock ring is 45 degrees. In this example, there is no angle restricting portion, and the material of the pipe is that the result (1) is a crosslinked polyethylene pipe and the result (2) is a polybutene pipe. From this experimental result, when the amount of biting of the holding claws 20 into the pipe 13 is less than 30%, the gripping force of the pipe 13 is reduced and the pipe comes out of the lock ring. On the other hand, if the amount of biting of the holding claws 20 into the pipe 13 exceeds 55%, the pipe breaks without extending. Therefore, the amount of biting of the holding claws 20 when the holding claws 20 of the lock rings 15 and 16 are erected in the same horizontal direction as the ring portion 19 is preferably 35 to 50% of the thickness cross-sectional area of the pipe 13. In particular, 40 to 50% is optimal.

  Table 2 shows the joint size 13A, the angle restriction value of the angle restriction portion 28 is divided into seven types from 0 degree to 30 degrees, and the test is performed. The thickness of the spacer ring 21 is 0.5 mm, 1.0 mm, 1 .. Divided into 4 types of 2 mm and 1.5 mm. As a result, as is apparent from the table, the angle restricting portion 28 with respect to the thickness of the spacer ring 21 is preferably provided at an angle of 10 to 15 degrees when the spacer thickness is 1.0 to 1.5 mm. It was possible to obtain the tensile performance of the simple pipe 13. Further, in the tests of the joint sizes 16A, 20A, etc., good results were obtained even when the angle restriction value was set to 5 to 10 degrees. Therefore, the restriction value of the angle restriction portion 28 was larger than 0 degrees, and the pipe was inserted. If the angle of refraction is smaller than the initial refraction angle of the holding claw 20 of the lock ring 15 attached to the mouth 29 side, the effect is more exhibited.

  Table 3 shows that the pipe tensile performance and insertability were tested by changing the separation distance A from 0.2 to 1.2 at a joint size of 13A and an angle regulation value of 30 degrees. The tensile performance is preferably 0.2 to 0.6 mm, and the insertability is good except for 0.2 mm. Overall, 0.4 to 0.6 is considered preferable. The insertability in Table 3 is indicated by x when the pipe could not be inserted into the joint, while the double circle indicates that the pipe could be inserted without applying excessive force.

It is the perspective view which showed an example of the pipe joint in this invention. It is the isolation | separation perspective view which isolate | separated and showed the pipe joint of FIG. It is the fragmentary sectional view which showed the pipe joint of FIG. (A), (b) is explanatory drawing which showed the pulling-out force of the pipe in this invention, and the deformation amount of a lock ring. It is a partial explanatory view showing the amount of bite into the pipe when the holding claw of the lock ring in the present invention stands up completely. (A), (b), (c) is explanatory drawing which showed the pipe insertion process of the pipe joint in this invention. It is the elements on larger scale of Fig.6 (a). (A), (b), (c) is a state explanatory drawing of a lock ring. (A) is the state which shape | molded the lock ring in planar shape. (B) is the state which bent the holding nail by bending. (C) is a state where the slit width becomes zero. It is the graph which showed the comparative example of the tensile test data of the pipe in the pipe joint of a crosslinked polyethylene pipe (PEX pipe). It is the graph which showed the comparative example of the tensile test data of the pipe in the pipe joint of a polybutene pipe (PB pipe). (A), (b), (c) is explanatory drawing for demonstrating the relationship between a pipe and a lock ring. (A), (b), (c) is explanatory drawing which showed the drawing-out force of the pipe in the prior art example, and the deformation amount of the lock ring. (A), (b) is explanatory drawing which showed the pipe insertion state of the pipe joint in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Joint main body 11 Joint member 12 Cover member 13 Pipe 15, 16 Lock ring 17, 18 Seal ring 19 Ring part 20 Holding claw 20b Recessed part 20c Biting part 21 Spacer ring 22 Mounting part 23 Mounting surface 24 Separation part 28 Angle regulation part

Claims (4)

The joint body is composed of a cylindrical joint member and a lid member, and a seal ring and a lock ring for preventing the insertion pipe from coming off are mounted in the joint body, and the lock ring is disposed so as to be able to rotate together with the insertion pipe. Characteristic pipe joint. The pipe joint according to claim 1, wherein the ring portion of the lock ring is inclined by 3 to 7 degrees with respect to a direction orthogonal to the central axis of the joint body. The pipe joint according to claim 1 or 2, wherein a holding claw is formed in an inclined manner on the inner periphery of the ring portion of the lock ring, and a separation portion is provided between the ring portion of the lock ring and a mounting portion in the joint body. . A pipe is formed by inclining the ring portion of the lock ring 3 to 7 degrees with respect to the direction orthogonal to the central axis of the joint body, and further inclining holding claws formed in an inclined manner on the inner periphery of the ring portion with respect to the ring portion. The pipe joint according to any one of claims 1 to 3 , wherein insertion of the pipe is easy and a pull-out preventing force of the pipe is obtained.

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