JP2011002012A - Pipe joint structure - Google Patents

Abstract

An object of the present invention is to make it possible to improve fatigue fracture resistance mainly by thermal expansion and contraction of a resin pipe joint.
A short tubular joint body 2 and a plurality of adhesive receiving portions 3 provided at the end of the joint main body 2, and the adhesive receiving portion 3 at the end of the resin pipe member 4 are provided. It is a pipe joint part structure configured to be capable of being inserted and fixed, and the adhesive receiving part 3 is a composite receiving part 11 having a resin material 14 that can be adhesively bonded to the resin pipe member 4 on its inner layer 12. The outer layer 13 of the composite receiving part 11 and the joint body 2 are made of a resin material 18 that can absorb the thermal expansion and contraction stress of the resin pipe member 4.
[Selection] Figure 1

Description

  The present invention relates to a pipe joint part structure.

  For example, a resin pipe joint 1 as shown in FIG. 6 is generally used for connecting resin pipes. Such a resin pipe joint 1 has a substantially short tubular joint body 2 and an adhesive receiving portion 3 (or receiving portion 3) provided at an end of the joint body 2. And the resin pipe member 4 can be easily connected by inserting, bonding, and fixing the end of the resin pipe member 4 (see FIG. 7) to the adhesive receiving portion 3 of the resin pipe joint 1. It is configured as follows. Examples of such a resin pipe joint 1 include, for example, an LT type as shown (having three adhesion receiving portions 3), and an L type (not shown) having two bonding receiving portions 3 (not shown). There are various kinds of things such as those having places.

  And the normal resin pipe joint 1 is comprised by the resin material of the single layer structure which consists of a resin material of the same kind as the resin pipe members 4 in order to enable the resin pipe members 4 to be bonded and fixed.

  When such a resin pipe member 4 and the resin pipe joint 1 are used, for example, in a piping part such as a drainage facility or a water supply / hot water supply facility for a building such as a house or a condominium, the temperature of the fluid flowing inside, The resin pipe joint 1 repeats thermal expansion and contraction together with the resin pipe member 4 due to the influence of the temperature and the like.

  Then, as shown in FIG. 7, the resin pipe joint 1 may cause fatigue failure due to repeated stress due to thermal expansion and contraction (fatigue failure portion 5). As shown in FIG. 8, such fatigue failure of the resin pipe joint 1 tends to occur frequently around the position 6 at the tip of the resin pipe member 4 inside the adhesion receiving portion 3. This is because the position 6 includes a flange portion 7 (expanded diameter portion) existing at a boundary portion between the joint body 2 and the adhesive receiving portion 3, and the resin pipe member 4 and the adhesive receiving portion 3 (adhesive). It is considered that stress concentration is likely to occur because the overall thickness is sharply reduced locally by being sandwiched between the adhesive portion 8 and the adhesive portion 8. .

  In order to prevent such fatigue failure due to repeated thermal expansion and contraction, conventionally, a rubber packing has been provided inside the receiving portion 3, and the resin pipe member 4 is inserted and held movably in the axial direction by this rubber packing. Various types of resin pipe joints 1 that can stop water while being proposed have been proposed (for example, see Patent Documents 1 to 4).

  In addition, the resin pipe joint 1 having such a rubber packing is provided with a stopper portion capable of defining the insertion position of the resin pipe member 4, thereby inserting the resin pipe member 4 into the receiving portion 3. It is also possible to reliably perform construction without causing excessive or insufficient insertion. Furthermore, the above-described stopper portion is configured such that the tip of the resin pipe member 4 can pass over when the resin pipe member 4 is extended (see Patent Document 3).

JP 2009-2476 JP 2008-106862 A JP 2006-31967 A Patent No. 2604445

  However, the conventional pipe joint has the following problems.

  That is, the above-described ordinary adhesive-bonding type resin pipe joint 1 configured as a single-layer resin material is simple and inexpensive, while it is the same type of resin as the resin pipe member 4. Since it was composed only of the material, there was a problem that it was not possible to fundamentally prevent the fatigue failure at the thickness-reducing shape portion subjected to repeated thermal expansion and contraction.

  The resin pipe joint 1 provided with a rubber packing, a stopper portion, etc. so as to be able to withstand fatigue failure due to repeated thermal expansion and contraction is an adhesively bonded resin pipe made of the resin material having the single-layer structure described above. Compared with the joint 1, there are problems that the structure is complicated, the price is expensive, and the water stoppage is lowered due to the aging of the rubber packing.

  In order to solve the above-mentioned problem, the invention described in claim 1 has a short tubular joint body and a plurality of adhesive receptacles provided at the ends of the joint body, and the adhesive receptacles. However, in the pipe joint part structure configured to be capable of inserting and fixing the end part of the resin pipe member, the adhesive receiving part has a resin material that can be adhesively bonded to the resin pipe member in its inner layer. The outer portion of the composite receiving portion and the joint body are made of a resin material capable of absorbing the thermal expansion and contraction stress of the resin pipe member.

  In the above, the invention described in claim 2 is characterized in that an inner layer and an outer layer of the composite receiving portion are fixed via an anchor structure portion.

  According to invention of Claim 1, the following effects can be acquired by the said structure. In other words, by using the composite receiving part as the adhesive receiving part, the inner layer and the outer layer of the adhesive receiving part can have different functions. In addition, the composite receiving part can be finished in the same shape as an adhesive receiving part having an ordinary single-layer structure, so it can be handled and constructed in the same way as a general resin pipe joint. It becomes possible to do. That is, no special handling or construction is required. The composite receiving part can be bonded and bonded to the resin pipe member by the resin material constituting the inner layer.

  Moreover, it becomes possible to absorb the thermal expansion-contraction stress of a resin pipe member by the resin material which comprises the outer layer of a composite opening part, and a coupling main body. That is, following the thermal expansion and contraction of the resin pipe member, the composite receiving portion and the joint main body can be expanded and contracted or deformed. Accordingly, it is possible to prevent fatigue failure due to repeated thermal expansion and contraction with a simple configuration without using a complicated structure including a rubber packing and a stopper portion.

  According to invention of Claim 2, the following effects can be acquired by the said structure. That is, since the inner layer and the outer layer of the composite receiving portion are fixed via the anchor structure portion, it is possible to maintain an integral strength between the inner layer and the outer layer. In addition, it is possible to ensure water-stopping between the inner layer and the outer layer.

It is a perspective view of the pipe joint part structure concerning the Example of this invention. FIG. 2 is a partial cross-sectional view of a pipe joint structure in which a resin pipe member is adhesively bonded to a composite receiving part of the pipe joint of FIG. 1. FIG. 3 is a perspective view of an inner layer member of the bonding port portion of FIG. 2. It is a perspective view of the modification of the inner layer member of the receptacle part for adhesion | attachment. It is a perspective view of the other modification of the inner layer member of the receptacle part for adhesion | attachment. It is a perspective view of the pipe joint part structure concerning a prior art example. It is a perspective view which shows the mode of the fatigue fracture which arises in FIG. It is a fragmentary sectional view of FIG.

  An object of the present invention is to make it possible to improve the fatigue fracture resistance due to thermal expansion and contraction of a resin pipe joint.

  Hereinafter, embodiments embodying the present invention will be described together with illustrated examples.

  1 to 5 show an embodiment of the present invention and a modification thereof.

  <Configuration> First, the configuration will be described.

  As shown in FIG. 2, the resin pipe joint 1 as shown in FIG. 1 can be used for adhesive connection of the resin pipe member 4 (see the adhesive portion 8 using an adhesive). The resin pipe joint 1 includes a short tubular joint body 2 and a plurality of adhesive receiving portions 3 provided at the end of the joint body 2. And it connects so that the resin pipe member 4 can be connected easily by inserting and fixing the edge part of the resin pipe member 4 with respect to the adhesion receiving part 3 of the resin pipe joint 1.

  Here, the diameter of the adhesive receiving port 3 is increased with respect to the joint main body 2 via the flange portion 7 (expanded diameter portion). The joint body 2 is configured such that its inner diameter is substantially equal to the inner diameter of the resin pipe member 4. In addition, the adhesive receiving port 3 as a whole is configured such that its inner diameter is substantially equal to the outer diameter of the resin pipe member 4.

  Examples of such a resin pipe joint 1 include, for example, an LT type as shown (having three adhesion receiving portions 3), and an L type (not shown) having two bonding receiving portions 3 (not shown). There are various kinds of things such as those having places. The above-described LT-type resin pipe joint 1 has a straight part and a branch / merging part in the joint body 2. The L-shaped resin pipe joint 1 has a bent portion in the joint body 2.

  Such a resin pipe member 4 and the resin pipe joint 1 are used, for example, in a piping section of a drainage facility or a water supply / hot water supply facility of a building such as a house or a condominium. In this case, the resin pipe joint 1 repeats thermal expansion and contraction together with the resin pipe member 4 due to the temperature of the fluid flowing inside the piping part, the influence of the outside air temperature, and the like. The thermal expansion and contraction of the resin pipe member 4 and the resin pipe joint 1 tends to be larger as it is provided on the upstream side of the pipe portion.

  In addition to the basic configuration as described above, the present embodiment has the following configuration.

  (1) The adhesive receptacle 3 has a resin material 14 (hereinafter referred to as an adhesive resin material 14 as necessary) on the inner layer 12 thereof and an outer layer 13 on the inner layer 12 thereof. The composite receiving portion 11 has a resin material 15 different from the resin material 14 (hereinafter referred to as a different resin material 15 if necessary). In particular, the outer layer 13 of the composite receiving portion 11 and the joint body 2 are capable of absorbing the thermal expansion and contraction stress of the resin pipe member 4 (hereinafter referred to as the elastic resin material 18 as necessary). ).

  Here, it is preferable to use the same kind of resin material as that of the resin pipe member 4 as the adhesive resin material 14 constituting the inner layer 12.

  For example, when the resin pipe member 4 is made of vinyl chloride resin, the adhesive resin material 14 is also made of vinyl chloride resin. More specifically, for example, the adhesive resin material 14 is made of a vinyl chloride polymer or a copolymer mainly composed of vinyl chloride.

  The adhesive resin material 14 constituting the inner layer 12 has a short cylindrical shape whose inner diameter is substantially equal to the outer diameter of the resin pipe member 4 and whose outer diameter is substantially equal to the inner diameter of the outer layer 13. Constitute. Moreover, you may make it provide the flange part 16 etc. which comprise the inner surface part of the above-mentioned flange part 7 as an stress reduction structure part in the inner end of the short cylinder-shaped inner layer 12.

  The dissimilar resin material 15 constituting the outer layer 13 is made an elastic resin material 18 that can expand or contract following the thermal expansion and contraction of the resin pipe member 4.

  Here, the elastic resin material 18 is preferably a resin material having a low elastic modulus and a large tensile breaking strain. Thus, by using a resin material having a low elastic modulus, it is possible to structurally reduce the stress generated by thermal expansion and contraction. The elastic modulus is preferably about 1/3 or less of the resin pipe joint 1 made of a resin material having a general single layer structure in order to function effectively. Further, by using a resin material having a large tensile fracture strain, it is possible to structurally improve the followability to deformation and displacement. The tensile breaking strain is preferably at least twice that of a resin pipe joint 1 made of a resin material having a general single-layer structure in order to function effectively.

  For example, when the resin pipe member 4 is made of vinyl chloride resin, the stretchable resin material 18 is made of polypropylene resin or polyethylene resin. More specifically, for example, the stretchable resin material 18 is composed of a propylene polymer or a copolymer mainly composed of propylene.

  In order for the stretchable resin material 18 to effectively expand and contract following the thermal expansion and contraction of the resin tube member 4, the stretchable resin material 18 is made to expand and contract the resin tube member 4. The amount of expansion / contraction is equal to or greater than the amount. The amount of expansion / contraction of the resin pipe member 4 can be obtained on the basis of the product of the length of the resin pipe member 4 and the thermal expansion (thermal contraction) coefficient.

  More specifically, for example, in the case of a product made of vinyl chloride resin, when the length of the resin tube member 4 is assumed to be 4 m which is one of the standard dimensions of the resin tube member 4, the resin tube member 4 The amount of expansion / contraction is about 20 mm. Therefore, in the case of a T-type or LT-type resin pipe joint 1 having two opposing composite receiving portions 11 at both ends of the straight portion of the joint body 2, the maximum amount of expansion and contraction is about 40 mm when the two places are combined. It will be necessary. Therefore, it is preferable that the stretchable resin material 18 is configured such that the amount of stretch at the time of breakage in the pull-out test is 40 mm or more. And in order to obtain the amount of expansion and contraction of 40 mm or more, the amount of expansion and contraction is insufficient only with the outer layer 13 of the composite receiving portion 11, so that the amount of expansion and contraction of the straight portion of the joint body 2 can also be used. Therefore, as described above, almost all of the resin pipe joint 1 including the outer layer 13, the joint body 2, and the flange portion 7 of the composite receiving portion 11 (excluding the inner layer 12) is made of the stretchable resin material 18. Consists of. In this case, in order to make it difficult for stress concentration to occur in the flange portion 7 which is the boundary between the joint body 2 and the composite receiving portion 11, as a stress reduction structure portion different from the above, it is more than a normal one. It is preferable to form a larger round portion 21 (ie, a large round portion) having a large curvature (that is, a curvature that can effectively reduce stress concentration). By adopting such a configuration, it is possible to employ the pipe joint 1 made of the upstream side with the most severe thermal expansion and contraction.

  (2) Furthermore, the inner layer 12 and the outer layer 13 of the above-described composite receiving portion 11 are fixed via the fixing portion 25.

  Here, the fixing | fixed part 25 can fix between the outer peripheral surface of the inner layer 12, and the inner peripheral surface of the outer layer 13 with respect to an axial direction and a circumferential direction.

  Further, when the flange portion 16 is provided on the inner layer 12, the fixing portion 25 can be provided between the inner surface of the flange portion 7 and the outer surface of the flange portion 16. In this case, the fixing portion 25 can fix the inner surface of the flange portion 7 and the outer surface of the flange portion 16 in the axial direction and the circumferential direction.

  The fixing portion 25 is referred to as the anchor structure portion 28 described above. The anchor structure portion 28 is configured by, for example, providing an uneven shape portion 29 between the inner layer 12 and the outer layer 13. The uneven portion 29 has a shape and an uneven amount (or protruding amount) that can function effectively as the anchor structure portion 28.

  For example, as shown in FIG. 2, the uneven portion 29 has an annular recess 32 that extends in the circumferential direction of the composite receiving portion 11, and an annular protrusion 33 that can be fitted into the annular recess 32 without a gap. Can be combined. The annular concave portion 32 and the annular convex portion 33 can be provided in a plurality of stages with an optimal interval with respect to the axial direction of the composite receiving portion 11. In this case, an annular recess 32 is provided in the outer layer 13, and an annular protrusion 33 is provided in the inner layer 12, as shown in FIG. However, these may be provided in reverse. That is, the annular protrusion 33 may be provided on the outer layer 13 and the annular recess 32 may be provided on the inner layer 12.

  The same uneven portion 29 can be provided between the inner surface of the flange portion 7 and the outer surface of the flange portion 16. In this case, an annular convex portion 33 is provided on the inner surface of the flange portion 7, and an annular concave portion 32 is provided on the outer surface of the flange portion 16. However, these may be provided in reverse. That is, the annular concave portion 32 may be provided on the inner surface of the flange portion 7 and the annular convex portion 33 may be provided on the outer surface of the flange portion 16. Note that the direction of protrusions and recesses (projection direction) of the uneven portion 29 is structurally a radial direction between the inner layer 12 and the outer layer 13, whereas an axis line between the flange portion 7 and the flange portion 16. Direction.

  In this case, the annular convex portion 33 has a protruding amount that is approximately half the thickness of the member (the inner layer 12 or the outer layer 13 or the flange portion 16) in which the annular concave portion 32 is provided. In order to prevent a decrease in strength around the flange portion 7, the annular convex portion 33 or the annular concave portion 32 is separated from the flange portion 7 that becomes a boundary between the joint body 2 and the composite receiving portion 11 (reduced strength). It is preferable that they are provided apart in the axial direction (only the distance necessary for prevention) (strength for preventing strength reduction or axial distance 34).

  In addition, as shown in FIG. 4, for example, the uneven portion 29 has an opening 41 and a fitting convex portion (not shown) that can be fitted to the opening 41 without a gap. can do. A plurality of the opening portions 41 and the fitting convex portions can be provided with an optimal interval in the circumferential direction of the composite opening portion 11. In this case, the outer layer 13 is provided with a fitting convex portion, and the inner layer 12 is provided with an opening 41. However, you may provide the opening part 41 and a fitting convex part in reverse. That is, the opening 41 may be provided in the outer layer 13 and the fitting convex portion may be provided in the inner layer 12. Further, the number and size of the openings 41 and the fitting protrusions can be set optimally.

  In this case, the fitting convex part has a protruding amount substantially equal to the thickness of the member (inner layer 12 or outer layer 13) in which the opening 41 is provided. Further, the opening 41 and the fitting convex portion are provided at four places with a phase of 90 degrees with respect to the circumferential direction of the composite opening portion 11. Each opening 41 and the fitting convex part are circular. However, each opening part 41 and the fitting convex part can have shapes other than circular shape.

  Moreover, the uneven | corrugated shaped part 29 can be used as the fitting recessed part and the fitting convex part 43 which can be fitted to this fitting recessed part without gap so that it may understand also from what was shown in FIG. A plurality of the fitting concave portions and the fitting convex portions 43 can be provided with an optimum interval in the circumferential direction of the composite opening portion 11. In this case, the outer layer 13 is provided with a fitting concave portion, and the inner layer 12 is provided with a fitting convex portion 43. However, the fitting concave portion and the fitting convex portion 43 may be provided opposite to each other. That is, the fitting convex portion 43 may be provided on the outer layer 13 and the fitting concave portion may be provided on the inner layer 12. In addition, the number and size of the fitting recesses and the fitting protrusions 43 can be set optimally.

  In this case, the fitting convex portion 43 has a protruding amount that is approximately half the thickness of the member (inner layer 12 or outer layer 13) provided with the fitting concave portion. The fitting concave portion and the fitting convex portion 43 are provided at four positions with a phase of 90 degrees with respect to the circumferential direction of the composite opening portion 11. Each fitting recessed part and the fitting convex part 43 are carrying out the rectangular shape. However, each fitting recessed part and the fitting convex part 43 are good also as shapes other than rectangular shape.

  Furthermore, although the uneven portion 29 is not particularly illustrated, it can be a combination of a screw hole and a screw groove. Or although the uneven | corrugated shaped part 29 is not specifically illustrated, it can also be made into a mesh shape, a knurled pattern, etc.

  Furthermore, the anchor structure 28 can also be combined with adhesion. In this case, the bonding can be performed using an adhesive (adhesion using an adhesive) or using heat generated during manufacturing (molding) (thermal bonding).

(3) Production of Resin Pipe Fitting 1 The inner layer 12 of the composite receiving part 11 and the outer layer 13 of the joint body 2 and the composite receiving part 11 are each formed by injection molding.

  In this case, the resin pipe joint 1 can be formed by insert molding. In the case of insert molding, the inner layer 12 made of an adhesive resin material 14 that has been injection-molded in advance is set in a mold, and then a stretchable resin material 18 is injected into the mold to injection-mold the joint body 2 and the outer layer 13. To do.

  The resin pipe joint 1 can be molded by two-color molding (multicolor molding). In the case of two-color molding (multicolor molding), the inner layer 12, the joint body 2, and the outer layer 13 described above are used for one type of mold by using a plurality of injection nozzles capable of separately injecting resin. The injection molding at the same time.

  Alternatively, the inner layer 12, the joint body 2 and the outer layer 13 are separately injection-molded, and fixed in combination by, for example, fitting or forcibly fitting the two in a later process to constitute the resin pipe joint 1. Etc. are also possible.

  When the resin pipe joint 1 is manufactured by the above-described insert molding or two-color molding (multicolor molding), the anchor structure portion 28 is thermally bonded. Further, when the resin pipe joint 1 is manufactured by the above-described fitting or forced fitting, it may be bonded to the anchor structure portion 28 with an adhesive. In the case of the insert molding described above, an adhesive can be applied to the inner layer 12 and placed.

(4) Coloring of the resin pipe joint 1 Either or both of the inner layer 12, the joint body 2 and the outer layer 13 described above can be made non-transparent or transparent. When both the inner layer 12 and the joint body 2 and the outer layer 13 are transparent, the inside of the resin pipe joint 1 can be observed from the outside. Thereby, it becomes possible to confirm the construction status of the resin pipe member 4 and the usage status of the piping portion by the transparent resin pipe joint 1. Further, when both the inner layer 12 and the joint body 2 and the outer layer 13 are made non-transparent, it is possible to finish in the same manner as the resin pipe joint 1 having a normal single layer structure. Also, depending on the purpose and application, it is possible to make one of the inner layer 12, the joint body 2 and the outer layer 13 non-transparent and the other transparent.

  <Operation> Next, the operation of this embodiment will be described.

  As described above, the resin pipe joint 1 in which the adhesive receiving portion 3 is the composite receiving portion 11 is formed by insert molding, two-color molding (multicolor molding), or fitting between the inner layer 12 and the outer layer 13. Or it is manufactured by forced fitting or the like.

  And this resin pipe joint 1 is used for piping parts, such as a drainage facility of buildings, such as a house and a condominium, and a water supply hot-water supply equipment, for example.

  That is, the resin pipe member 4 is connected by inserting, fixing, and fixing the end of the resin pipe member 4 to the adhesion receiving portion 3 of the resin pipe joint 1. At this time, the end portion of the resin pipe member 4 is inserted and fixed to the adhesive resin material 14 of the inner layer 12 of the composite opening 11.

  According to this embodiment, the following operational effects can be obtained.

  (1) By using the adhesive receiving port 3 as the composite receiving port 11, the inner layer 12 and the outer layer 13 of the bonding receiving port 3 can have different functions. In addition, the composite receiving portion 11 can be finished in the same shape as an adhesive receiving portion having a normal single-layer structure, so that it is handled and constructed in the same manner as a general resin pipe joint. It becomes possible to do. That is, no special handling or construction is required. The composite receiving portion 11 can be bonded and bonded to the resin pipe member 4 by the resin material 14 (adhesive resin material 14) constituting the inner layer 12 thereof.

  Further, the resin material 18 (stretchable resin material 18) constituting the outer layer 13 of the composite receiving portion 11 and the joint body 2 can absorb the thermal expansion and contraction stress of the resin pipe member 4. That is, following the thermal expansion and contraction of the resin pipe member 4, the composite receiving portion 11 and the joint body 2 can be expanded and contracted or deformed. Accordingly, it is possible to prevent fatigue failure due to repeated thermal expansion and contraction with a simple configuration without using a complicated structure including a rubber packing and a stopper portion.

  (2) Since the inner layer 12 and the outer layer 13 of the composite receiving portion 11 are fixed via the anchor structure portion 28, it is possible to maintain an integral strength between the inner layer 12 and the outer layer 13. It becomes. In addition, it is possible to ensure water blocking between the inner layer 12 and the outer layer 13.

  For example, it becomes possible to provide a resin pipe joint having a high fatigue resistance against fatigue due to thermal expansion and contraction for piping parts such as a drainage facility and a hot water supply facility for buildings such as houses and condominiums.

2 Joint body 3 Adhesive receiving portion 4 Resin pipe member 11 Composite receiving portion 12 Inner layer 13 Outer layer 14 Resin material (adhesive resin material)
15 Resin material (stretchable resin material or dissimilar resin material)
18 Resin material (stretchable resin material)
28 Anchor structure

Claims (2)

It has a short tubular joint body and a plurality of adhesive receiving portions provided at the end of the joint main body, and the adhesive receiving portion is configured so that the end of the resin pipe member can be inserted, bonded and fixed. In the pipe joint structure,
The adhesive receiving portion is a composite receiving portion having a resin material that can be adhesively bonded to the resin pipe member on the inner layer thereof,
An outer layer of the composite receiving part and the joint body are made of a resin material capable of absorbing thermal expansion and contraction stress of the resin pipe member.   The pipe joint part structure according to claim 1, wherein an inner layer and an outer layer of the composite receiving part are fixed via an anchor structure part.

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