JP4994110B2 - Method for manufacturing flexible pipe joint - Google Patents

Description

  The present invention relates to a method for manufacturing a flexible pipe joint used for connecting a drain pipe for a house, etc., and a helical or ring-shaped linear reinforcing member can be easily and accurately positioned on a molding die, suppressing deformation. It can be efficiently formed integrally with the tube body.

  Flexible pipe fittings are used as joints for miscellaneous drainage pipes for apartment houses such as apartment buildings and single-family houses, and they absorb misalignment between pipes, connect bent parts, or are in the event of an earthquake. Used for damage prevention and seismic isolation.

  Conventionally, flexible pipe joints have a bellows structure, and are generally made flexible by making the inner and outer wall surfaces of the pipe uneven, and the inner diameter is reduced by the unevenness of the inner wall surface. In addition to being reduced by that amount, when the flow rate of drainage is small, drainage, solids, etc. tend to accumulate in the recesses, and bad odors are likely to occur.

  Accordingly, various flexible pipe joints have been proposed that can smooth the inner wall surface and prevent drainage from staying. For example, a soft cylindrical body with a smooth inner wall surface and a hard ring on the outer peripheral surface of the cylindrical body. There has been proposed a flexible pipe joint that is integrally formed by separating them in the axial direction (see Patent Document 1).

Also, as shown in FIG. 4, a flexible tube composed of a soft tube main body 1 and a reinforcing member 2 spirally embedded in the outer periphery thereof has been proposed (see Patent Documents 2 and 3).
JP 2005-172186 A JP 2001-241574 A Japanese Utility Model Publication No. 47-33851

  However, when manufacturing such a flexible pipe joint, after molding a rigid ring or a helical reinforcing member with a synthetic resin or the like in advance by blow molding, injection molding, or extrusion molding, A spiral reinforcing member is set in a mold for molding, filled with a synthetic resin for a soft cylindrical body, and molded. In the case of a spiral reinforcing member, to the mold However, in the case of using a hard ring, there is a problem that the setting to the mold must be repeated as many times as necessary, which requires a lot of man-hours and cannot be efficiently manufactured.

  Also, if a hard ring or a spiral reinforcing member is integrally formed on the outer periphery of a soft cylindrical body, deformation is likely to occur after molding due to the difference in hardness of materials such as resin, especially when a hard ring is provided in parallel. There is a problem that deformation is more likely to occur because the rings are independent and not connected to each other as compared to the spiral reinforcing member connected to one.

  Furthermore, in a flexible pipe joint in which hard rings are arranged in parallel, an axial through-hole or protrusion is provided on the hard ring to improve the adhesion between the hard ring and the soft tubular body. The resin material is allowed to enter (see Patent Document 1), and the inner diameter becomes smaller by the amount of the axial through hole or protrusion. Therefore, if the required inner diameter is ensured, the outer diameter of the flexible fitting increases. There is also.

  The present invention has been made in view of the problems of the prior art, and can be easily set on a mold or the like, and can be prevented from being deformed after molding even if a material having a hardness difference is used, and the outer diameter is compact. It is an object of the present invention to provide a method of manufacturing a flexible pipe joint that can be made.

In order to solve the above-described problems of the prior art, a flexible pipe joint manufacturing method according to claim 1 of the present invention includes a pipe body having connecting portions at both ends, and a spiral shape or a plurality of pipe bodies provided on the outer periphery of the pipe body. When manufacturing flexible pipe joints composed of the ring-shaped linear reinforcing member of the pipe body and the linear reinforcing member having different hardnesses,
After integrally forming the linear reinforcing member with a synthetic resin through a runner communicating with the spiral portion or each ring-shaped portion, the linear reinforcing member is positioned and fixed by the runner, and the tube body is made of synthetic resin. It is characterized by being integrally formed.

According to this method of manufacturing a flexible pipe joint, the pipe main body includes a pipe main body having a connecting portion at both ends and a spiral or plural ring-shaped linear reinforcing member provided on the outer periphery of the pipe main body. When manufacturing a flexible pipe joint with different hardness of the linear reinforcing member,
After integrally forming the linear reinforcing member with a synthetic resin through a runner communicating with the spiral portion or each ring-shaped portion, the linear reinforcing member is positioned and fixed by the runner, and the tube body is made of synthetic resin. It is designed to be integrally molded, leaving the runner used for molding the linear reinforcement member as it is, and using it for positioning and fixing when molding the tube body, making it easy to set on a mold etc. The rigidity is increased so that deformation due to a hardness difference after molding can be prevented.

  According to a second aspect of the present invention, there is provided a method for manufacturing a flexible pipe joint, wherein in addition to the configuration of the first aspect, a connecting hole and / or groove is formed in the linear reinforcing member, The connecting hole and / or groove is filled with the synthetic resin of the tube main body.

  According to this method for manufacturing a flexible pipe joint, a connecting hole and / or groove is formed in the linear reinforcing member, and the synthetic resin of the pipe body is placed in the connecting hole and / or groove. The connection hole or groove, or the hole and groove improves the adhesion between the linear reinforcing member and the pipe body, and the connection hole or groove, or the hole and groove is formed into the linear member itself. It can be made compact by forming.

  According to the method for manufacturing a flexible pipe joint according to claim 1 of the present invention, a pipe body having a connecting portion at both ends, and a spiral or plural ring-shaped linear reinforcement provided on the outer periphery of the pipe body When manufacturing flexible pipe joints composed of members and having different hardnesses between the pipe body and the linear reinforcing member, the linear reinforcing member is connected to the spiral portion or the runner communicating with each ring-shaped portion through a synthetic resin. Since the linear reinforcing member is positioned and fixed by the runner after the integral molding with the synthetic resin, the pipe main body is left as it is for molding the linear reinforcing member. By using it for positioning and fixing at the time of molding, it is possible to facilitate setting to a mold or the like, and to enhance the rigidity by a runner and prevent deformation due to a hardness difference after molding.

  According to the method for manufacturing a flexible pipe joint according to claim 2 of the present invention, a connecting hole and / or groove is formed in the linear reinforcing member, and the connecting hole and / or Since the groove is filled with the synthetic resin of the tube main body, the adhesion between the linear reinforcing member and the tube main body is improved by the connecting hole or groove or the hole and groove, and the connecting hole or groove or hole is improved. By forming the groove in the linear member itself, it can be made compact.

  Hereinafter, an embodiment of a method for producing a flexible pipe joint of the present invention will be described in detail with reference to the drawings.

  1 to 3 relate to an embodiment of a method for manufacturing a flexible pipe joint according to the present invention, and FIG. 1 is a straight and right-angled shape showing a cut-out portion of the manufactured flexible pipe joint. FIG. 2 is a schematic perspective view of the linear reinforcing member after molding, and FIG. 3 is a schematic perspective view of the linear reinforcing member when the pipe body is molded.

  The flexible pipe joint 10 manufactured by the method for manufacturing a flexible pipe joint according to the present invention is used, for example, as a joint between housing drain pipes or a joint such as a drain pipe and an appliance, and has a normal diameter of 30. Used for piping in the range of ~ 90 mm.

  The flexible pipe joint 10 includes a pipe main body 11 having smooth inner and outer surfaces, and both ends of the pipe main body 11 are provided with connecting portions 11a with pipes, for example, attached to the outside of the pipe and fixed with bands. Thus, it is formed slightly larger in diameter than the piping. A spiral linear reinforcing member 12 made of a material having a higher hardness than that of the tube body is provided on the outer periphery of the tube body 11 to constitute a flexible tube joint 10.

  The tube body 11 is made of, for example, a soft vinyl chloride resin, has a thickness of 1 to 3 mm, and is integrally formed with the connecting portions 11a at both ends.

  The connecting portion 11a is not limited to a type inserted on the outside of the tube and pressed by a band or the like, but one end portion is formed with a small taper shape and the other end portion is formed with a large diameter taper shape to be fitted and bonded together. Other formats such as a format to be used may be used.

  If the thickness of the tube body 11 is less than 1 mm, the tube body 11 may be broken or damaged, and the durability is inferior. On the other hand, when the thickness exceeds 3 m, the flexibility is lowered.

  The linear reinforcing member 12 provided on the outer periphery of the tube main body 11 is made of, for example, hard vinyl chloride resin, has a hardness difference of about 50 to 20 with a JISK6253 type A durometer, and has both ends connected in an annular shape. It is formed in a spiral shape having a ring portion 12a.

  For example, as shown in FIG. 1B, such a flexible pipe joint 10 is provided between pipes P arranged at right angles, and pushes the pipe body 11 and the linear reinforcing member 12 in the axial direction. As it shrinks, the connecting portions 11a at both ends are inserted so as to cover the pipes P and P, and a band is wound around the outer periphery to be fastened and fixed.

  Thus, in the state where the flexible pipe joint 10 is attached to the right-angled bent portion, the interval between the spirals 12b of the linear reinforcing member 12 inside the bent portion is reduced, while the interval between the outer spirals 12b is increased. However, in this flexible pipe joint 10, the tube main body 11 and the linear reinforcing member 12 are formed of materials having different hardness, the tube main body 11 is soft, and the linear reinforcing member 12 is hard. 11 can be in a bent state without being crushed, and the wall surface 11b of the tube body 11 inside the bent portion protrudes and overlaps so as to be pushed outward, so that the inner surface of the pipe joint can be kept almost flat. . Thereby, the waste water etc. which flow through the inside do not accumulate, and it does not cause a bad odor.

  Next, the manufacturing method of such a flexible pipe joint 10 will be specifically described. First, after the linear reinforcing member 12 is, for example, injection-molded, it is placed in a mold, and the pipe body 11 and It is molded by integrating the linear reinforcing member 12 and the pipe body 11 by injection molding with the synthetic resin.

  In other words, a mold (not shown) for forming the linear reinforcing member 12, the ring portion 12 a and the forming portion of the spiral 12 b, the gate 13 on both sides of the forming portion of the spiral 12 b, and the runners on both sides communicating with each gate 13. 14 and the resin filling port 15 are formed, and injection molding is performed using a synthetic resin having a high hardness for the linear reinforcing member 12, for example, a hard vinyl chloride resin.

  Then, as shown in FIG. 2, the molded intermediate linear reinforcing member 12 </ b> A is a rod-like runner connected with gates 13 on both sides of the linear reinforcing member 12 with hard vinyl chloride resin filled from the resin filling port 15. 14 and 14 and an unnecessary portion where the resin from the resin filling port 15 to the one runner 14 is integrated.

  Usually, in order to obtain the linear reinforcing member 12, an excess portion is removed from the intermediate linear reinforcing member 12A after molding and used for the next molding. Here, as shown in FIG. The gate 13 and the rod-like runners 14 and 14 connecting them are left as they are, and only the portion from the resin filling port 15 to the runner 14 at the tip is removed.

  In this way, the linear reinforcing member 12 provided with the rod-like runners 14 and 14 on both sides is also used as a support rod for the runners 14 and 14 and set in a mold (not shown) for forming the tube main body 11. A synthetic resin having a low hardness that becomes the tube main body 11, for example, a soft vinyl chloride resin, is injected into and integrated with the inner peripheral portion.

  Since the runners 14 and 14 are left on both sides of the linear reinforcing member 12 during the injection molding for integrating the tube main body 11 and the linear reinforcing member 12, the linear reinforcing member 12 is placed at a predetermined position. It is fixed and can be molded into a predetermined shape without rotating around the central axis by the injection pressure and without changing the spiral interval.

  In addition, when the tube main body 11 is injection-molded and taken out of the mold, the tube main body 11 and the linear reinforcing member 12 try to be deformed due to a difference in hardness. The runners 14, 14 on both sides of the linear reinforcing member 12 function as support rods, can increase the rigidity of the linear reinforcing member 12, and can prevent deformation after molding due to a difference in hardness. It can be formed into a shape.

  Further, in this method of manufacturing the flexible pipe joint 10, the pipe body 11 and the linear reinforcing member 12 are made of the same synthetic resin, vinyl chloride resin, and the amount of plasticizer added is changed to provide a hardness difference. Therefore, the adhesiveness between the tube main body 11 and the linear reinforcing member 12 can be enhanced and integrated. Thereby, the deformation | transformation after shaping | molding can be prevented further using the rigidity of the linear reinforcement member 12 effectively.

  In addition, the manufacturing method of this flexible pipe joint 10 is not restricted to the case where the pipe main body 11 and the linear reinforcing member 12 are configured by giving a hardness difference with vinyl chloride resin, but the pipe main body 11 and the linear reinforcing member 12. May be made of different synthetic resins, or other materials such as rubber and elastomer may be used, as long as they have a hardness difference.

  Further, in the method for manufacturing the flexible pipe joint 10, as shown in FIGS. 2 and 3, a connecting groove 16 and a hole 17 are formed in the linear reinforcing member 12. The flexible pipe joint 10 is formed with a concave groove 16 facing the inner peripheral side at a position corresponding to the gate 13, and a concave long groove 16 on the outer peripheral side at a position orthogonal to the concave groove 16. A hole 17 penetrating the inner and outer peripheries communicating with the long groove 16 is formed. Thereby, when the synthetic resin of the pipe body 11 is injected and filled when the pipe body 11 is formed, the resin enters the groove 16 and the hole 17 for connection, and the linear reinforcing member 12 and the pipe body 11 are bonded. Can be improved.

  In this method of manufacturing the flexible pipe joint 10, the connecting groove 16 and the hole 17 are formed at the height of the linear reinforcing member 12 itself in the inner and outer circumferential directions. Therefore, the groove 16 and the hole 17. Thus, the inner diameter of the tube main body 11 is not reduced and the outer diameter of the linear reinforcing member 12 is not increased, and the flexible pipe joint 10 itself can be made compact.

  In the above embodiment, both the connecting groove 16 and the hole 17 are formed in the linear reinforcing member 12 to improve the adhesiveness with the tube main body 11, but only one of them is formed. You may do it.

  Further, the case where the linear reinforcing member 12 has a spiral shape and is provided with a ring portion at both ends has been described as an example. However, the present invention is not limited to this, and a spiral shape without a ring portion or a plurality of ring shapes are spaced apart. It is also possible to configure with a plurality of rings, and even when using these multiple rings, the required number of flexible pipe joints are integrally formed with a gate and a runner, and the runner is also used as a support rod. You can do that.

It is the linear and right-angled front view which cut and show a part of the manufactured flexible pipe joint concerning one Embodiment of the manufacturing method of the flexible pipe joint of this invention. It is a schematic perspective view after shaping | molding of the linear reinforcement member concerning one Embodiment of the manufacturing method of the flexible pipe joint of this invention. It is a schematic perspective view of the linear reinforcement member at the time of shaping | molding of the pipe main body concerning one Embodiment of the manufacturing method of the flexible pipe joint of this invention. It is sectional drawing which notched a part of conventional flexible pipe joint.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flexible pipe joint 11 Pipe main body 11a Connection part 11b Wall surface 12 Reinforcement member 12a Ring part 12b Spiral 13 Gate 14 Runner 15 Resin filling port 16 Connection groove | channel 17 Connection hole P, P Piping

Claims (2)

A flexible tube comprising a tube main body having a connecting portion at both ends and a spiral or plural ring-shaped linear reinforcing member provided on the outer periphery of the tube main body, and the hardness of the tube main body and the linear reinforcing member differ. When manufacturing fittings,
After integrally forming the linear reinforcing member with a synthetic resin through a runner communicating with the spiral portion or each ring-shaped portion, the linear reinforcing member is positioned and fixed by the runner, and the tube body is made of synthetic resin. A method for manufacturing a flexible pipe joint, wherein the flexible pipe joint is integrally formed.   2. A connecting hole and / or groove is formed in the linear reinforcing member, and the connecting hole and / or groove is filled with a synthetic resin of the tube main body. The manufacturing method of the flexible pipe joint as described.

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