JP5147377B2 - 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, and the like, which can be easily bent and applied, and can prevent deformation during molding.

  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.

  Therefore, various flexible pipe joints have been proposed that can smooth the inner wall surface and prevent stagnation of drainage. For example, as shown in FIG. 4, the tubular body 1 made of a low elastic resin is made of a norbornene resin. There has also been proposed a flexible tubular body in which the linear reinforcing member 2 is provided spirally with respect to the tubular body 1 (see Patent Document 1).

In addition, a soft cylindrical main body having a smooth inner wall surface and a flexible pipe joint in which a hard ring is integrally formed on the outer peripheral surface of the cylindrical main body while being separated in the axial direction have been proposed (see Patent Document 2). .
JP 2001-241574 A JP 2005-172186 A

  However, in such a flexible pipe joint, when used in a 90 ° bent portion, the tubular body between the spiral reinforcing members and between the hard rings is compressed inside the bent portion, while the outside of the bent portion. However, since the tubular body has a uniform thickness, it is difficult to bend and the construction is difficult to perform.

  In addition, when a reinforcing member of a spiral or hard ring 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 the case of flexible pipe joints in which hard rings are arranged in parallel, when connecting pipes, after pressing and shrinking and inserting between the pipes, the connecting parts at both ends are respectively inserted into the pipes. There is also a problem that an operator must attach it while stretching it, because only the repulsive force due to the elasticity of the soft cylindrical body acts.

The present invention has been made in view of the problems of the prior art, and can be easily bent and installed. In addition to providing a helical reinforcing member, deformation after molding can be achieved even when materials having a hardness difference are used. An object of the present invention is to provide a method of manufacturing a flexible pipe joint that can be prevented and that can be easily constructed by utilizing the repulsive force.

In view of the above problems, as a result of intensive studies on flexible pipe joints, it is easy to bend due to the difference in hardness between the tube body and the helical reinforcing member, the space between the spirals, the longitudinal cross-sectional shape of the tube body, and the like. It has been found that there is a structure that can prevent deformation after molding due to a difference in hardness even if it is a reinforcing member, and the manufacturing method of the present invention has been completed, and its specific configuration is as follows.

That is, in order to solve the above-mentioned problems of the prior art, a flexible pipe joint manufacturing method according to claim 1 of the present invention comprises a pipe body having connecting portions at both ends and having substantially smooth inner and outer surfaces, A flexible pipe joint manufacturing method comprising a reinforcing member provided in a spiral shape on the outer periphery of a main body, wherein the flexible pipe joint is formed by molding the reinforcing member in advance and then placing it in a mold. The tube body is injection molded to form the reinforcing member and the tube body integrally. The tube body and the reinforcing member are made of synthetic resins having different hardnesses, and the tube While the hardness of the main body is set to 70 to 30 (JISK6253 type A durometer), the surface of the tube main body between the spirals of the reinforcing member is formed on two inclined surfaces with a lower central portion, and the inclined surface The base end wall thickness is set to 1 to 3 mm. The member has a hardness of 100 to 80, is formed in a spiral shape having a ring portion in which both end portions of the reinforcing member are connected in an annular shape, and a space between the spirals is set to 10 to 25 mm. .
According to this method for manufacturing a flexible pipe joint , after the reinforcement member is injection molded in advance, the reinforcement member and the pipe body are integrated by installing in the mold and injection molding the tube body. in molded, the hardness and wall thickness of the pipe body as well as these values, the surface between the helix of the pipe body middle part and lower two inclined surfaces, the distance between the hardness and the helical reinforcing members of these values By facilitating bending by facilitating internal and external deformation of the bent part, the construction is facilitated, and the both ends of the spiral are annular ring parts, thereby increasing the rigidity of the reinforcing member and after molding due to the hardness difference In addition, the repulsive force of the reinforcing member is generated in the extending direction even when the sheet is compressed, thereby facilitating attachment to the pipe and improving workability.

According to a second aspect of the present invention, there is provided a flexible pipe joint manufacturing method comprising the pipe body and the reinforcing member made of the same synthetic resin in addition to the structure of the first aspect. To do.
According to this flexible pipe joint manufacturing method , the pipe body and the reinforcing member are made of the same synthetic resin, so that the adhesiveness between the pipe body and the reinforcing member can be increased and integrated.

Furthermore, the manufacturing method of the flexible pipe joint according to claim 3 of the present invention is characterized in that, in addition to the structure according to claim 1 or 2, the pipe body is made of a transparent resin or a colored transparent resin. Is.
According to this flexible pipe joint manufacturing method , the pipe body is made of a transparent resin or a colored transparent resin, so that the mounting state during construction can be confirmed and the visibility of dirt and the like can be improved. I have to.

Moreover, in addition to the structure in any one of Claims 1-3, the manufacturing method of the flexible pipe joint of Claim 4 of this invention made the cross-sectional shape of the spiral of the said reinforcing member the trapezoid shape. It is characterized by this.
According to this method for manufacturing a flexible pipe joint , the cross-sectional shape of the spiral of the reinforcing member is made trapezoidal, thereby preventing interference between the distal ends of the reinforcing member when bent. The required strength and rigidity can be secured with the minimum amount of material used.

According to the method for manufacturing a flexible pipe joint according to the first aspect of the present invention, a pipe body having a connecting portion at both ends and having a substantially smooth inner and outer surfaces, and a spiral body provided on the outer periphery of the pipe body. A method for manufacturing a flexible pipe joint comprising a reinforcing member , wherein the flexible pipe joint is formed by injection molding the reinforcing member in advance, and then placing the reinforcing member in a molding die, and the pipe main body is injection molded. Thus, the reinforcing member and the tube body are formed integrally, the tube body and the reinforcing member are made of synthetic resins having different hardnesses, and the tube body has a hardness of 70 to 30 (JISK6253). On the other hand, the surface of the tube main body between the spirals of the reinforcing member is formed on two inclined surfaces whose central part is lowered, and the base wall thickness of the inclined surface is 1 to 3 mm. And the hardness of the reinforcing member is 100-80 The installation the ends of the reinforcing member is formed in a spiral shape having a ring portion which is connected in a ring form, since the interval between the spiral and 10 to 25 mm, after they were injection molded in advance reinforcing member, in to the mold Then, the tube body is injection-molded to form the reinforcing member and the tube body integrally. The hardness and thickness of the tube body are set to these values, and the surface between the spirals of the tube body is formed. By setting the slope of the central part to a low slope and the hardness of the reinforcing member and the space between the spirals to these values, the longitudinal cross-sectional shape of the two slopes of the tube body facilitates deformation inside and outside the bent portion and makes it easy to bend. And can be easily constructed. In addition, since both ends of the spiral are ring-shaped ring portions, the rigidity of the reinforcing member can be increased, so that deformation after molding due to a difference in hardness can be prevented, and the reinforcing member can be extended in the extending direction even when compressed. A repulsive force can be generated, and attachment to piping can be facilitated and workability can be improved.

According to the method for manufacturing a flexible pipe joint according to claim 2 of the present invention, since the pipe body and the reinforcing member are made of the same synthetic resin, the adhesion between the pipe body and the reinforcing member is improved. Can be integrated. As a result, deformation after molding can be further prevented, and the repulsive force by the reinforcing member can be effectively applied.

Furthermore, according to the method for manufacturing a flexible pipe joint according to claim 3 of the present invention, the pipe body is made of a transparent resin or a colored transparent resin. While being able to confirm, visibility, such as dirt, can be improved and maintenance management etc. can be performed appropriately.

According to the method for manufacturing a flexible pipe joint according to claim 4 of the present invention, since the cross-sectional shape of the spiral of the reinforcing member is trapezoidal, the tip of the reinforcing member in the bent state is used. Interference between the parts can be prevented, the bending angle can be increased, and necessary strength and rigidity can be ensured with a minimum amount of material used.

Hereinafter, an embodiment of a method for producing a flexible pipe joint according to 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 front view, a side view, and a cutaway view showing a part of the manufactured flexible pipe joint . 2 is a partially enlarged cross-sectional view, FIG. 2 is a front view of only the reinforcing member of the manufactured flexible pipe joint, and FIG. 3 is a cross-sectional view showing a part of the manufactured flexible pipe joint being bent at 90 degrees. FIG.

The flexible pipe joint 10 manufactured by the manufacturing method of the present invention is used, for example, as a joint between residential drain pipes or a joint between a drain pipe and an appliance, and a pipe having a normal diameter of 30 to 100 mm. Used for etc.
The flexible pipe joint 10 is composed of a pipe body 11 and a reinforcing member 12 that reinforces the pipe body 11, and connection parts 11 a with pipes P are provided at both ends of the pipe body 11. It is formed in a slightly larger diameter than the pipe P so as to be attached to and fixed with a band.
The connecting portion 11a is not limited to the type inserted into the outside of the pipe P and pressed with a band or the like, but has one end with a small taper and the other with a large taper. Other types such as a bonding type may be used.

  As shown in FIG.1 (c), the pipe body 11 is made into two inclined surfaces 11c and 11c where the inner surface is smooth, and the outer surface is low in the central portion 11b between the spirals of the spiral reinforcing member 12, The lower portion of the central portion 11b is spirally continuous between the reinforcing members 12.

The tube body 11 is made of, for example, soft vinyl chloride resin, olefin resin, urethane resin, elastomer resin, or the like, has a hardness of 70 to 30 (JISK6253 type A durometer), and is integrally formed with the connecting portions 11a at both ends. . The tube body 11 has a thickness of 1 to 3 mm at the thickest portion that is the base end portion of the inclined surface 11c, and the center portion 11b has a thickness that is about 0.5 mm thinner than the base end portion. is there.
When the thickness of the base end portion of the inclined surface 11c of the tube body 11 is less than 1 mm, the tube body 11 may be broken at the inclined central portion 11b, and the durability is inferior. On the other hand, when the thickness of the base end portion of the inclined surface 11c exceeds 3 mm , the flexibility is lowered and bending becomes difficult. Moreover, when the hardness of the tube body 11 is less than 30, the tube body 11 is easily deformed, the pressure resistance is insufficient, and the pressure of the reinforcing member 12 may not be able to be endured. On the other hand, when the hardness exceeds 70, flexibility is lowered and bending becomes difficult.

  In this way, the thickness of the inclined base end portion is made by providing the two inclined surfaces 11c and 11c in which the outer surface of the central portion 11b in the tube axis direction is low between the spirals of the tube main body 11 and both sides between the spirals are highly inclined. Compared to the above, it is possible to increase the stretchability as much as the thickness of the central portion 11b is thin, and thereby the tube body 11 can be easily bent.

The spiral reinforcing member 12 is provided on the outer periphery of the tube main body 11, and is formed of a material having higher hardness than the tube main body 11 to constitute the flexible pipe joint 10.
The reinforcing member 12 provided on the outer periphery of the tube body 11 is formed of a hard vinyl chloride resin, an olefin resin, a urethane resin, an elastomer resin or the like, and has a hardness of 100 to 80 (JISK6253 type A durometer). Are formed in a spiral shape having a ring portion 12a connected in a ring shape.

  By forming ring portions 12a that are annularly connected to both ends of the reinforcing member 12, the rigidity in the central axis direction and the torsional direction rigidity with respect to the central axis can be increased even in a spiral shape. It becomes easy to effectively prevent deformation after forming the different tube main body 11 and the reinforcing member 12 integrally, and to make the shape as designed.

  And the space | interval D of the spiral 12b of the helical reinforcement member 12 shall be 10-25 mm, and the wall surface of the pipe main body 11 of the part of this space | interval D is made into the state exposed to the outer peripheral side, and the two inclined surfaces 11c and 11c are made into the state. Is formed.

  Further, the cross-sectional shape of the spiral 12b of the reinforcing member 12 is trapezoidal, the bottom is wide, and the top is narrow, thereby preventing interference between the distal ends of the reinforcing member 12 when bent. In addition, the necessary strength and rigidity are ensured with the minimum amount of material used. The cross-sectional shape of the spiral 12b is, for example, in the range where the width of the bottom is 6 to 10 mm and the width of the top is 2 to 4 mm, and the height is preferably about 3 to 8 mm. If the height is less than 3 mm, the strength is insufficient. If the height is more than 8 mm, the tip portions interfere with each other, which hinders bending and is not preferable.

  If the hardness of the reinforcing member 12 exceeds 100, the brittleness cannot be ensured, and if the hardness is less than 80, the shape of the tube body 11 may not be maintained. Further, if the spiral distance D of the reinforcing member 12 is less than 10 mm, the spirals 12b and 12b may interfere with each other when bent. If the spiral distance D exceeds 25 mm, the tube body 11 is reinforced. There is a risk that the reinforcing function to be reduced.

  For example, as shown in FIG. 3, the flexible pipe joint 10 configured as described above is provided between pipes P and P arranged at right angles so as to compress and contract the pipe body 11 and the reinforcing member 12 in the axial direction. Then, 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 tightened and fixed.

  In this state, when the flexible pipe joint 10 is attached to the right-angled bent portion, the distance D between the spirals 12b of the reinforcing member 12 inside the bent portion is narrowed while the distance D between the outer spirals 12b is widened. However, in this flexible pipe joint 10, the tube body 11 and the reinforcing member 12 are formed of materials having different hardnesses, the tube body 11 is soft, the reinforcing member 12 is hard, and the hardness is the tube body. 70 to 30 (JISK6253 type A durometer), 100 to 80 with the reinforcing member 12, the interval between the spirals 12b to 10 to 25 mm, and the tube body 11 between the spirals 12b and 12b to have two inclined lower central portions 11b Since the surfaces 11c and 11c are provided, the tube main body 11 is easily expanded and contracted by the two inclined surfaces 11c and 11c, and can be easily bent.

  Moreover, according to this flexible pipe joint 10, the rigidity of the reinforcement member 12 can be improved by making the both ends of the spiral 12b into an annular ring part 12a, and the pipe joint can be compressed and compressed when attached. In addition to the repulsive force due to the elasticity of the tube body 11 in the stretching direction, the repulsive force due to the reinforcing member 12 is generated, and all of these can be used to stretch the pipe joint. The attachment of the joint 10 can be facilitated and the workability can be improved.

  Furthermore, such a flexible pipe joint 10 is formed by, for example, previously molding the reinforcing member 12 in advance, then placing the reinforcing member 12 in a molding die, and injection-molding the pipe body 11, whereby the reinforcing member 12 and the pipe body 11. However, when the tube body 11 is taken out of the mold after the injection molding of the tube body 11, it may be deformed due to a difference in hardness between the tube body 11 and the reinforcing member 12. In the pipe joint 10, since the reinforcing member 12 is formed in a spiral shape having a ring portion 12a in which both ends are connected in an annular shape, the rigidity of the reinforcing member 12 can be increased and deformation after molding due to a hardness difference can be prevented. Can be formed into a predetermined shape.

  Moreover, according to this flexible pipe joint 10, since the cross-sectional shape of the spiral 12b of the reinforcing member 12 is trapezoidal, it is possible to prevent interference between the distal ends of the reinforcing member 12 when bent. In addition, the required strength and rigidity can be ensured with a minimum amount of material used compared to a rectangular cross section having a width at the bottom.

  Next, in this flexible pipe joint 10, the pipe body 11 and the reinforcing member 12 are made of the same synthetic resin, and are configured to have a hardness difference by adding an additive such as a plasticizer. The adhesiveness between the tube main body 11 and the reinforcing member 12 can be improved and integrated. As a result, the rigidity of the reinforcing member 12 can be effectively used to further prevent deformation after molding, and the repulsive force of the reinforcing member 12 can be effectively applied during construction to facilitate the construction. It is also possible to integrate without using an agent or the like.

  Furthermore, in this flexible pipe joint 10, if the pipe body 11 is made of a transparent resin such as vinyl chloride resin or a colored transparent resin, the state of insertion into the pipe P can be seen from the outside at the time of construction. It can be easily constructed, and dirt and the like can be easily seen from the outside, so that maintenance management and the like can be performed appropriately.

  The flexible pipe joint 10 is not limited to the case where the pipe body 11 and the reinforcing member 12 are configured with the same synthetic resin having a difference in hardness, but the pipe body 11 and the reinforcing member 12 are formed of different synthetic resins. Alternatively, other materials such as rubber and elastomer may be used.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example 1)
The pipe body of the flexible pipe joint is made of soft vinyl chloride resin, the hardness is 70 (JISK6253 type A durometer), the thickness of the thickest part of the base end of the inclined surface is 2.0 mm, and the central portion of the inclined surface The wall thickness was reduced to 0.5 mm by 1.5 mm.
The reinforcing member was made of hard vinyl chloride resin, the hardness was 100, the helix interval was 15 mm, the helix bottom width was 8 mm, the helix top width was 3.0 mm, and the helix height was 5.0 mm.
The reinforcing member was formed by injection molding in advance. Thereafter, after setting the reinforcing member in the mold, the resin of the pipe body was injected to obtain a flexible pipe joint as a unit.
The obtained flexible pipe joint was bent at an angle of 90 degrees, and the state at that time was visually observed and evaluated in four stages. ◎: very good, ○: good, Δ: somewhat good, × : Bad.
As shown in Table 1, the result was good and the pipe body was strong, but could be bent without any trouble in construction.

(Example 2)
A flexible pipe joint was obtained in the same manner as in Example 1 except that the hardness of the pipe body was 50.
As shown in Table 1, the result was very good, there was no deformation of the spiral portion, it was bent well, and the strength of the tube body was sufficient.

Example 3
A flexible pipe joint was obtained in the same manner as in Example 1 except that the hardness of the pipe body was set to 30.
As shown in Table 1, the result was good, there was no deformation of the spiral portion, it was bent easily, and the strength of the tube body was lowered, but it was sufficient.

Example 4
A flexible pipe joint was obtained in the same manner as in Example 2 except that the hardness of the reinforcing member was 80.
As shown in Table 1, the result was good, there was a slight deformation in the spiral portion, and the strength was reduced, but it was sufficient.

(Example 5)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the thickness of the inclined base end portion of the pipe body was 1 mm.
As shown in Table 1, the result was good and could be bent easily, and the strength of the tube body was lowered but sufficient.

Example 6
A flexible pipe joint was obtained in the same manner as in Example 2 except that the thickness of the pipe body was 3 mm.
As shown in Table 1, the result was good and the tube body was strong, but could be bent without any problem.

(Example 7)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the spiral interval was 10 mm.
As shown in Table 1, the result was very good, and the spiral portion was not deformed and could be bent easily.

(Example 8)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the spiral interval was 25 mm.
As shown in Table 1, the result was good and could be bent easily.

Example 9
A flexible pipe joint was obtained in the same manner as in Example 2 except that the width of the top of the spiral was 8 mm.
As shown in Table 1, the results were slightly good and slightly difficult to bend, but there was no problem in construction.

(Comparative Example 1)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the hardness of the reinforcing member was 70.
As shown in Table 1, the result was poor, the spiral portion was not strong, and buckled when bent.

(Comparative Example 2)
A flexible pipe joint was obtained in the same manner as in Examples 1 and 2 except that the hardness of the pipe body was 80.
As shown in Table 1, the result was poor, and it was difficult to bend even when trying to bend.

(Comparative Example 3)
A flexible pipe joint was obtained in the same manner as in Examples 1 and 2, except that the hardness of the pipe body was 20.
As shown in Table 1, the result was poor and the strength of the tube body was insufficient.

(Comparative Example 4)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the thickness of the pipe body was 5.0 mm.
As shown in Table 1, the result was poor, the tube body was strong, and could not be bent.

(Comparative Example 5)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the thickness of the pipe body was 0.5 mm.
As shown in Table 1, the result was poor and was torn when the tube body was bent.

(Comparative Example 6)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the spiral interval was 8 mm.
As shown in Table 1, the results were poor, the bending angle was limited, and the use was hindered.

(Comparative Example 7)
A flexible pipe joint was obtained in the same manner as in Example 2 except that the spiral interval was 30 mm.
As shown in Table 1, the result was inferior, and when bent, reinforcement between the spirals of the tube body was not made.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view, a side view, and a partially enlarged cross-sectional view showing a part of a manufactured flexible pipe joint according to an embodiment of a method for manufacturing a flexible pipe joint of the present invention. It is a front view only of the reinforcement member of the manufactured flexible pipe joint concerning one Embodiment of the manufacturing method of the flexible pipe joint of this invention. It is sectional drawing which notches and shows a part of the state which bent the manufactured flexible pipe joint concerning one Embodiment of the manufacturing method of the flexible pipe joint of this invention at 90 degree | times. 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 Center part 11c Inclined surface 12 Reinforcement member 12a Ring part 12b Spiral D Spiral spacing P, P Piping

Claims (4)

A method of manufacturing a flexible pipe joint comprising a pipe body having a connecting portion at both ends and a substantially smooth inner and outer surface, and a reinforcing member spirally provided on the outer periphery of the pipe body,
The flexible pipe joint is formed by pre-injecting the reinforcing member, and then placing the reinforcing member in a mold and injection-molding the pipe main body, thereby integrating the reinforcing member and the pipe main body. Molded with
The pipe body and the reinforcing member are made of synthetic resins having different hardnesses,
While the hardness of the tube body is set to 70 to 30 (JISK6253 type A durometer), the surface of the tube body between the spirals of the reinforcing member is formed on two inclined surfaces with a lower central portion, and The base end wall thickness of the inclined surface is 1 to 3 mm,
The reinforcing member has a hardness of 100 to 80, is formed in a spiral shape having a ring portion in which both end portions of the reinforcing member are connected in an annular shape, and a space between the spirals is set to 10 to 25 mm. Manufacturing method of flexible pipe joint. The method for manufacturing a flexible pipe joint according to claim 1, wherein the pipe body and the reinforcing member are made of the same synthetic resin. 3. The method for manufacturing a flexible pipe joint according to claim 1, wherein the pipe body is made of a transparent resin or a colored transparent resin. The method for manufacturing a flexible pipe joint according to any one of claims 1 to 3, wherein the reinforcing member has a trapezoidal cross-sectional shape.

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