JP2005330983A - Mechanical pipe fitting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent coming-out of a connector pipe from a pipe fitting, even if the pipe is made of a material of any hardness. <P>SOLUTION: In this mechanical pipe fitting, a fall-stopper member 5 is provided with an annular holder 16 arranged along the inner peripheral surface 2b of a cap nut 2 to hold a spherical body 15, and the inner peripheral surface 16b of the holder 16 is formed with a claw part 17 projecting toward the peripheral surface 6a of the connector pipe 6. When fastening the cap nut 2 to a fitting main body 1, since the spherical body 15 and the claw part 17 are pushed to the peripheral surface 6a of the connector pipe 6 at the same time, any one or both of the spherical body 15 and the claw part 17 bite the peripheral surface 6a of the connector pipe 6. With this structure, when external force in the drawing direction is applied to the connector pipe 6, any one or both of the spherical body 15 and the claw part 17 bite the peripheral surface 6a of the connector pipe 6 with wedging work of the holder 16 to the cap nut 2, and fall of the connector pipe 6 can be thereby prevented independently of material of the connector pipe 6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pipe joint, and more particularly to a mechanical pipe joint that can connect various connection pipes such as a steel pipe or a resin pipe by preventing the connection pipe from coming out of the pipe joint.

  As pipe joints used for indoor pipes or buried pipes, for example, Patent Document 1 and Patent Document 2 below disclose mechanical pipe joints that connect metal pipes such as stainless steel pipes. These mechanical pipe joints have a tubular joint body having a threaded portion at the end, a threaded portion that is screwed into the threaded portion of the joint body, and a cap nut that has a tapered surface that expands in the direction of insertion of the metal tube. And a seal member disposed inside the joint body and mounted on the outer peripheral surface of the metal tube, and a retaining member disposed inside the cap nut and abutted against the tapered surface. The retaining member includes a sphere pressed against the outer peripheral surface of the metal tube and a holding body that is disposed along the inner peripheral surface of the cap nut and holds the sphere. When the cap nut is tightened into the threaded part of the joint body, the sphere is bitten into the metal tube when the sphere is pressed against the outer peripheral surface of the metal tube by the tapered surface of the cap nut and an external force is generated to pull out the connection tube. The wedge action prevents the metal tube from being pulled out.

  The following Patent Document 3 discloses a mechanical pipe joint in which a retaining member constituting the sphere is applied to a lining pipe whose outer peripheral surface of a metal pipe is coated with a resin. In this pipe joint, when the cap nut is fastened to the joint body, the sphere is pressed against the lining layer made of resin of the lining pipe, and the lining pipe is prevented from being pulled out by the wedge action of the sphere that has digged into the lining layer.

  However, the retaining member using a sphere can prevent pulling out due to the wedge action of the sphere that bites into the connecting pipe when the connecting pipe is formed of a relatively hard material such as metal. In the case of being formed only with a material having a relatively low hardness, such as a wedge, the wedge action by the sphere is not sufficiently generated, and the drawing cannot be prevented. That is, the resin tube of low hardness material made of polybuden, cross-linked polyethylene, polyethylene, or the like is soft so that when an external force is generated to pull out the resin tube, the resin tube is easily deformed and the sphere of the retaining member becomes a resin. There is a drawback in that the surface of the resin pipe is slid without almost biting into the pipe. Therefore, in the pipe joints of Patent Documents 1 to 3, a sufficient pull-out preventing effect cannot be obtained with respect to the resin pipe with only a low pull-out preventing force corresponding to the compressive deformation generated on the surface of the resin pipe by the sphere.

  On the other hand, the following Patent Document 4 discloses a mechanical pipe joint that can connect a resin pipe by preventing the connection pipe from coming out of the pipe joint. In this mechanical pipe joint, the retaining member is formed by a metal split ring that is arranged along the inner peripheral surface of the cap nut and has a plurality of biting teeth that protrude toward the outer peripheral surface of the resin pipe on the inner peripheral surface. Composed. The bite teeth of the metal split ring bite into the outer peripheral surface of the resin pipe by tightening the pipe joint and prevent the resin pipe from coming out of the pipe joint. In Patent Document 4, since the biting teeth are formed of a material harder than the resin tube, the biting teeth can be bitten into the resin tube to prevent the resin tube from being pulled out.

Japanese Utility Model Publication No. 3-49351 JP 2003-172484 A Japanese Utility Model Publication No. 3-53105 Japanese Utility Model Publication No. 49-62215

  However, in the mechanical pipe joint of Patent Document 4, the biting teeth of the retaining member are formed of a resin material or metal that is harder than the resin material that forms the connection pipe, but for example, on a hard connection pipe such as a stainless steel pipe When the pipe joint was attached, the biting teeth protruding from the metal split ring had low mechanical strength and were crushed when pressed against the connecting pipe and did not bite into the connecting pipe. Moreover, with the deformed bite tooth, a sufficient pulling-in preventing force cannot be obtained, and a highly reliable mechanical pipe joint could not be formed.

  In order to solve the above-mentioned conventional problems, the present inventor individually configured a retaining member having a sphere and a retaining member having a biting tooth, and applied to any of a metal tube and a resin tube. Although a mechanical pipe joint that can be used has been developed, the two retaining members have caused an increase in the size of the cap nut and an increase in the number of components due to an increase in the arrangement space of the retaining member in the cap nut. Further, the existing mechanical pipe joint has a problem that a plurality of retaining members cannot be arranged.

  Therefore, an object of the present invention is to provide a mechanical pipe joint that can prevent a connecting pipe having any hardness from coming out of the joint body by a retaining member. Another object of the present invention is to provide a mechanical pipe joint that can prevent an increase in the size of the cap nut due to the retaining member and an increase in the number of parts of the pipe joint. It is another object of the present invention to provide a mechanical pipe joint including a retaining member that can be easily applied to an existing cap nut or joint body.

  The mechanical pipe joint of the present invention includes a joint body (1) having a body thread portion (11) formed at the end (1c), and a nut screw that is screwed into the body thread portion (11) of the joint body (1). A cap nut (2) having a tapered surface (13) formed with a portion (12) and having a diameter increasing in a direction of insertion through the connection pipe (6), and disposed inside the joint body (1) and connected to the connection pipe (6) A seal member (3) that contacts the outer peripheral surface (6a), and a retaining member (5) that contacts the tapered surface (13) and that is disposed inside the cap nut (2). When the nut screw part (12) of the cap nut (2) is tightened into the main body screw part (11) of the fitting body (1), the retaining member (5) is prevented by the tapered surface (13) of the cap nut (2). The connection pipe (6) is pressed against the outer peripheral surface (6a) to prevent the connection pipe (6) from coming out of the joint body (1). The retaining member (5) includes a spherical body (15) pressed against the outer peripheral surface (6a) of the connecting pipe (6) and a cap nut when the nut screw portion (12) is tightened into the main body screw portion (11). An annular holder (16) disposed along the tapered surface (13) of (2) and holding the sphere (15), and further projecting toward the outer peripheral surface (6a) of the connecting pipe (6) The part (17) is provided on the inner peripheral surface (16b) of the holding body (16). Insert the connection pipe (6) through the cap nut (2) and fitting body (1), and tighten the nut screw (12) of the cap nut (2) into the screw thread (11) of the fitting body (1). At this time, the retaining member (5) in the cap nut (2) is pressed by the tapered surface (13) of the cap nut (2) and connects either or both of the spherical body (15) and the claw portion (17). The outer peripheral surface (6a) of the pipe (6) can be securely bited. For example, in the case of a connecting pipe (6) made of a material such as a relatively hard metal, when an external force is applied to pull out the connecting pipe (6), the wedge action of the holding body (16) against the cap nut (2) The claw portion (17) and the sphere (15) are further pressed against the connecting pipe (6). At this time, the claw portion (17) does not bite into the connecting pipe (6) largely or hardly bites, but the sphere (15) bites into the outer peripheral surface (6a) of the connecting pipe (6), so that the connecting pipe (6) The escape from the joint body (1) can be prevented. In contrast, in the case of the connecting pipe (6) made of a material such as a resin having a relatively low hardness, when an external force is applied to pull out the connecting pipe (6), the wedge of the holding body (16) against the cap nut (2) By the action, the claw portion (17) and the sphere (15) are further pressed against the connecting pipe (6). At this time, the outer peripheral surface (6a) of the connecting pipe (6) is deformed, and the spherical body (15) does not bite or hardly bites into the outer peripheral surface (6a) of the connecting pipe (6). Since the outer peripheral surface (6a) of the connecting pipe (6) is securely bited, the connecting pipe (6) can be prevented from coming off from the joint body (1). Therefore, when the connecting pipe (6) is connected by a pipe joint, the retaining member (5) can prevent the connecting pipe (6) of any hardness or material from coming out of the joint body (1). . Further, since the claw portion (17) is formed on the holding body (16) of the retaining member (5) that holds the sphere (15), the sphere (15) and the claw are formed by the tapered surface (13) of the cap nut (2). The cap nut (2) can be pressed at the same time against the outer peripheral surface (6a) of the connecting pipe (6), and the cap nut (2) can be enlarged by increasing the arrangement space of the retaining member (5) in the cap nut (2). And the increase in the number of parts which comprise a pipe joint can be prevented.

  The mechanical pipe joint according to the present invention can sufficiently connect the connection pipe with high reliability by sufficiently preventing the connection pipe from coming out of the pipe joint regardless of the type of the connection pipe. Moreover, it is not necessary to replace the pipe joint or the retaining member in accordance with the type of the connecting pipe to be connected, and the workability is excellent.

Embodiments of the mechanical pipe joint according to the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the mechanical pipe joint is disposed inside the tubular joint body (1), the cap nut (2) screwed to the joint body (1), and the joint body (1). An annular seal member (3) mounted on the outer peripheral surface (6a) of the connecting pipe (6) and a retaining member (5) disposed inside the cap nut (2) are provided. The joint main body (1) formed of a metal material or resin material mainly made of a casting such as iron or stainless steel has a cylindrical central portion (1d) for guiding a fluid such as water flowing in the connection pipe (6). And an end portion (1c) formed with an enlarged diameter relative to the center portion (1d) and connected to the cap nut (2), and an end screw (1c) formed on the outer peripheral surface (1a), for example, a male screw And a main body screw portion (11).

  As with the joint body (1), the cap nut (2) formed of a metal material or resin material mainly made of cast iron such as iron or stainless steel has a body screw of the joint body (1) on the inner peripheral surface (2b). A nut thread portion (12) that is, for example, an internal thread, screwed into the portion (11), and a tapered surface (13) that expands toward the joint body (1) side, that is, in a direction through which the connection pipe (6) is inserted. And a stepped portion (14) having a radial shoulder (14a) and an axial annular inner surface (14b) formed between the nut screw portion (12) and the tapered surface (13). Note that the connecting portion of the joint body (1) and the cap nut (2) may be structured in a manner that the main body screw portion is a female screw and the cap nut screw portion is a male screw, contrary to the above.

  The sealing member (3) formed by a resin gasket or packing is disposed in close contact with the inner peripheral surface (1b) that forms the expanded internal space at the end (1c) of the joint body (1). Also, it closely adheres to the outer peripheral surface (6a) of the connecting pipe (6) inserted through the joint body (1). An annular washer (4) formed of a material such as iron, stainless steel or resin has an axial direction between the stepped portion (14) of the cap nut (2) and the end (1c) of the joint body (1). It is pinched so that it cannot move. As shown in FIG. 1, the washer (4) disposed adjacent to the seal member (3) on the inner side of the cap nut (2) is constituted by, for example, a washer or the like, and includes a joint body (1) and a cap nut (2 ), The cap nut (2) is smoothly rotated during the final tightening, and the seal member (3) is prevented from moving. In the present embodiment, the washer (4) has a convex portion formed annularly along the outer peripheral surface and protruding from the outer peripheral surface, and the convex portion is connected to the stepped portion (14) of the cap nut (2) and the joint. It is clamped by the end (1c) of the main body (1).

  As shown in FIG. 2, the retaining member (5) disposed inside the cap nut (2) is formed in an annular holding body (16) having a substantially wedge cross-sectional shape and a holding body (16). A sphere (15) disposed in each of the plurality of spherical recesses (16c). The holding body (16) is made of, for example, a resin such as ABS resin or polyacetal resin, a corrosion-resistant metal such as stainless steel, a normal metal, or the like. Although not shown, when the holding body (16) is passed through the connecting pipe (6), a notch (cutting part) is formed in a part of the annular holding body (16) so that the diameter of the holding body (16) is freely expanded. (Or joint) (20) (Fig. 3). Therefore, the holding body (16) can be formed of a metal split ring whose diameter is reduced by pressing the tapered surface (13) of the cap nut (2).

  The holding body (16) includes an outer peripheral surface (16a) formed with an inclined surface (19) inclined along the tapered surface (13) of the cap nut (2), and an outer peripheral surface of the connecting pipe (6) to be inserted. Between the inner peripheral surface (16b) formed substantially parallel to (6a) and the outer peripheral surface (16a) and the inner peripheral surface (16b), formed substantially perpendicular to the outer peripheral surface (6a) of the connecting pipe (6). A front surface (16d) and a back surface (16e). A claw portion (17) projecting toward the outer peripheral surface (6a) of the connection pipe (6) is provided on the inner peripheral surface (16b) of the holding body (16), and the claw portion (17) is a back surface of the holding body (16). (16e) is formed continuously. As shown in FIG. 3, the claw portion (17) is formed in an annular shape continuously in the circumferential direction on the inner peripheral surface (16b) of the holding body (16), and as shown in FIG. 2, the inclined surface (17a) And a back surface (16e) of the holding body (16) and a vertical plane (17b) that is coplanar with a triangular cross-sectional shape. The claw portion (17) may be integrally formed of the same material as the holding body (16), but after being formed of the same or different material as the holding body (16), the inner peripheral surface of the holding body (16) ( It may be fixed to 16b). For example, the claw portion (17) formed of metal may be embedded in the holding body (16) formed of resin by molding.

  The spherical body (15) is formed of iron or stainless steel or the like, and is exposed from the outer peripheral exposed portion (15a) exposed from the outer peripheral surface (16a) of the holding body (16) and the inner peripheral surface (16b) of the holding body (16). An exposed inner peripheral exposed portion (15b). The opening diameter of the spherical recess (16c) on the inner peripheral surface (16b) side is smaller than the diameter of the sphere (15), and the sphere (15) arranged in the spherical recess (16c) rotates into the spherical recess (16c). Holds possible and non-detachable. The sphere (15) is embedded in the spherical recess (16c) by molding (injection molding) or the like in a state of being arranged at a predetermined position. The tip of the claw portion (17) is formed close to the outer peripheral surface (6a) of the connection pipe (6) with a smaller diameter than the inner peripheral exposed portion (15b) of the sphere (15). The inner peripheral exposed portion (15b) may be formed closer to the outer peripheral surface (6a) of the connecting pipe (6) than the claw portion (17) or close to the same.

  When connecting the pair of connecting pipes (6) by the mechanical pipe joint of the present invention, the connecting pipe (6) is connected to the cap nut (2), the annular retaining member (5), the washer (4), and the seal member. After passing through (3), the joint body (1) is appropriately screwed into the temporarily tightened state shown in FIG. At this time, the claw portion (17) of the retaining member (5) does not contact the outer peripheral surface (6a) of the connecting pipe (6) or the outer peripheral surface (6a) of the connecting pipe (6) is inclined (17a). Slide on the top. The spherical body (15) rolls or slides when the inner peripheral exposed portion (15b) does not contact the outer peripheral surface (6a) of the connecting pipe (6) or contacts the outer peripheral surface (6a) of the connecting pipe (6). Guide the internal movement of the connecting pipe (6) while moving. The holding body (16) is easily expanded in diameter by the notch (20), and the sphere (15) rolls or slides on the tapered surface (13) and the outer peripheral surface (6a) of the connecting pipe (6). The connecting pipe (6) can be smoothly and easily inserted through the joint body (1).

  After inserting the connecting pipe (6) into the joint body (1) at the specified position, turn the cap nut (2) and connect the nut screw (12) of the cap nut (2) to the body of the joint body (1). Tighten to the threaded part (11). Since the cap nut (2) moves toward the joint body (1), the holding body (16) is a space on the opening (21) side reduced in diameter by the tapered surface (13) in the cap nut (2). Relatively close to For this reason, the tapered surface (13) is pressed while sliding on the inclined surface (19) of the holding body (16), and the holding body (16) is reduced in diameter radially inwardly to connect the connecting pipe (6). Press the outer peripheral surface (6a). At this time, since the outer periphery exposed portion (15a) abuts the tapered surface (13), the inner periphery exposed portion (15b) is connected to the connection tube while rolling or sliding against the frictional force. The outer peripheral surface (6a) of (6) is pressed radially inward. The claw portion (17) presses the outer peripheral surface (6a) of the connecting pipe (6) radially inward together with the inner diameter of the holding body (16) to be contracted. For this reason, the outer peripheral exposed portion (15a) of the sphere (15) is pressed inward by the tapered surface (13) so that the inner peripheral exposed portion (15b) bites into the outer peripheral surface (6a) of the connecting pipe (6) or The claw portion (17) of the holding body (16) bites into the outer peripheral surface (6a) of the connecting pipe (6), and the outer peripheral surface (6a) of the connecting pipe (6) has a partially spherical or linear or dotted line-shaped concave portion. (6b) is formed. In this way, one of the spherical body (15) and the claw portion (17) can be surely bited into the outer peripheral surface (6a) of the connecting pipe (6), but as shown in FIG. 1, the connecting pipe (6) Of course, the claw portion (17) and the sphere (15) may bite into the outer peripheral surface (6a) of the lens at the same time. The holding body (16) provided with the notch (20) is easily reduced in diameter, and the sphere (15) rolls or slides on the tapered surface (13) and the outer peripheral surface (6a) of the connecting pipe (6). The cap nut (2) can be screwed smoothly and easily into the joint body (1). In the present embodiment, the holding body (16) can be easily expanded or contracted by the notch (20).

  When an external force is applied to the connecting pipe (6) in the direction of withdrawal of the pipe joint, the holding body (16) is further reduced in diameter by the wedge action of the holding body (16) against the tapered surface (13), and the claw portion (17 ) And the sphere (15) further bite into the outer peripheral surface (6a) of the connecting pipe (6). For this reason, it is possible to reliably prevent the connecting pipe (6) from slipping out by the retaining prevention force generated by the biting of one or both of the claw portion (17) and the spherical body (15). For example, when the connecting pipe (6) is formed of a metal material having high hardness, the claw portion (17) is deformed and hardly or not bites into the connecting pipe (6), but the sphere (15) is connected to the connecting pipe (6). Therefore, the connecting pipe (6) can be prevented from coming off from the joint body (1). On the other hand, when the connecting pipe (6) is formed of a low-hardness resin material, the outer peripheral surface (6a) of the connecting pipe (6) is recessed inside and escapes, so that the sphere (15) is connected to the connecting pipe (6). Little or no biting into the outer peripheral surface (6a) and no stopping force due to the sphere (15), but the claw part (17) bites into the outer peripheral surface (6a) of the connecting pipe (6). The connection pipe (6) can be prevented from coming off from the main body (1). Therefore, the connecting pipe (6) of any hardness or material can be connected well by preventing the connecting member (5) from coming off from the joint body (1) by the retaining member (5).

  In the present embodiment, the claw portion (17) is formed on the holding body (16) of the retaining member (5) that receives the wedge action of the cap nut (2), and the spherical recess (16c) of the holding body (16). Since the sphere (15) is placed inside the cap nut (2), the cap nut (2) is increased in size and the number of parts constituting the pipe joint is increased by increasing the arrangement space of the retaining member (5). Can be prevented.

  The embodiment of the present invention is not limited to the embodiment shown in FIGS. 1 to 4 and can be changed. For example, instead of continuously forming the claw portion (17) along the back surface (16e) of the holding body (16), it may be provided continuously along the front surface (16d) of the holding body (16). Further, as shown in FIG. 5, two claw portions (17) may be provided on the inner peripheral surface (16b) of the holding body (16). The number of claw parts (17) is not limited, and it is also possible to arrange three or more claw parts (17) on the inner peripheral surface (16b) of the holding body (16). Further, the claw portion (17) may be provided more centrally on the inner peripheral surface (16b) without being continuously provided on the back surface (16e) or the front surface (16d) of the holding body (16).

  The shape of the claw portion (17) is not limited to the triangular cross-sectional shape, and when the inclined surface (19) of the holding body (16) is pressed by the tapered surface (13) of the cap nut (2), the connecting pipe ( If it bites into the outer peripheral surface (6a) of 6), it can be changed appropriately. As shown in FIG. 6, a plurality of claw portions (17) may be formed on the inner peripheral surface (16b) of the holding body (16) at intervals in the circumferential direction. The outer periphery exposed portion (15a) of the sphere (15) is accommodated in the spherical recess (16c) and is not exposed from the holding body (16), but only the inner periphery exposed portion (15b) contacting the connecting pipe (6) is held. It may be exposed from the body (16).

  Although not shown, the mechanical pipe joint is provided with the other joint body, a cap nut, a tightening member, a seal member and a washer symmetrically about the central portion (1d) of the joint body (1), and two connecting pipes. (6) can be linked. Therefore, in the mechanical pipe joint of the present invention, two connection pipes having different hardnesses can be coupled by a single pipe joint. It goes without saying that the structure of the mechanical pipe joint of the present invention can be applied to other shapes such as elbows other than straight pipes.

  A mechanical pipe joint shown in FIG. 1 is formed as Example 1, a mechanical pipe joint shown in FIG. 5 is formed as Example 2, and a retaining member that has only a sphere and does not have a claw as Comparative Example 1 The mechanical type pipe joint provided with the retaining member which has only a nail | claw part and does not provide a spherical body as a comparative example 2 was formed. In Example 1, Example 2, Comparative Example 1 and Comparative Example 2, a stainless pipe having a nominal diameter of 20 mm and a cross-linked polyethylene pipe having a nominal diameter corresponding to a nominal diameter of 20 mm, a polyethylene pipe and a polybutene pipe having the same connecting pipe (6 )It was used. As shown in FIG. 7, the mechanical pipe joint of Example 1 has a retaining member (5) having an inner circumference D1 having a diameter of 23.9 mm and a minor diameter outer circumference D2 having a diameter of 26.7 mm. The length L1 is 8.5 mm, the thickness L2 from the outer circumference on the major axis side to the tip of the claw portion (17) is 5.4 mm, the thickness L3 from the inner circumference to the tip of the claw portion (17) is 1.2 mm, The inclination angle θ of the claw part (17) with respect to the back surface (16e) of the holding body (16) was 40 degrees, and the diameter D3 of the sphere (15) was 4.0 mm. In the retaining member (5) of the first embodiment, the tip of the claw portion (17) is closer to the outer peripheral surface (6a) of the connection pipe (6) than the inner peripheral exposed portion (15b) of the sphere (15). . The holding body (16) was made of ABS resin, and the claw portion (17) was formed integrally with the holding body (16) from the same material. The spherical body (15) was formed of stainless steel and was rotatably held by the holding body (16). The mechanical pipe joint of Example 2 is composed of the same material and dimensions as those of the mechanical pipe joint of Example 1, but as shown in FIG. 5, the inner peripheral surface (16b) of the holding body (16) Two claw portions (17) were provided. On the other hand, the mechanical pipe joint of Comparative Example 1 is composed of the same material and dimensions as the mechanical pipe joints of Example 1 and Example 2, and the inner peripheral surface of the spherical body is exposed on the inner peripheral surface of the holding body. Protruding, but no nail part was provided. The mechanical pipe joint of Comparative Example 2 is composed of the same material and dimensions as the mechanical pipe joints of Example 1 and Example 2 as in Comparative Example 1, and the claw portion protrudes from the inner peripheral surface of the holding body. However, no sphere was provided. With respect to Example 1, Example 2, Comparative Example 1 and Comparative Example 2, the pull-out preventing force of the connecting pipe (6) was measured and compared.

  In the practical test, the claw portion (17) provided in the retaining member (5) of Examples 1, 2 and Comparative Example 2 is crushed and bites into the outer peripheral surface when pressed against the outer peripheral surface of the stainless steel tube. However, when pressed against the outer peripheral surfaces of the cross-linked polyethylene pipe, polyethylene pipe, and polybden tube, they could bite into the outer peripheral surface. In addition, the sphere (15) provided in the retaining member (5) of Example 1, Example 2 and Comparative Example 1 could bite into the outer peripheral surface when pressed against the outer peripheral surface of the stainless steel tube. When pressed against the outer peripheral surfaces of the crosslinked polyethylene pipe, the polyethylene pipe and the polybutene pipe, the outer peripheral face was deformed into a hemispherical shape, but could not be bitten.

  The connecting pipe (6) is connected to each mechanical pipe joint, and Table 1 shows the measurement results of the pulling-in preventing force of the connecting pipe (6) using a tensile tester (not shown).

  From the measurement results, the mechanical pipe joint of the present invention shown in Example 1 and Example 2 has a good pulling prevention force as in the case of the conventional mechanical pipe joint shown in Comparative Example 1 with respect to a stainless steel pipe having high hardness. At the same time, it is clear that a good pull-out preventing force is exhibited for a crosslinked polyethylene pipe, a polyethylene pipe and a polybden pipe having a low hardness. Moreover, Example 2 which provided the two nail | claw part (17) in the internal peripheral surface (16b) of the holding body (16) shows a result better than Example 1 about a resin pipe. Resin pipes are easy to deform, so the pull-out prevention force is lower than stainless steel pipes, but in resin pipes through which fluid flows, the deformation resistance of the pipe is increased by the fluid, so that a higher pull-out prevention force than the values shown in Table 1 occurs. It is estimated to be. Therefore, the mechanical pipe joint of the present invention has a higher pulling prevention force than the conventional mechanical pipe joint, and the connecting pipe (6) of any hardness can be pulled out from the joint body (1) by the retaining member (5). It was found that can be prevented.

  The mechanical pipe joint according to the present invention can be favorably applied to pipe joints used for pipes of water, oil, steam, air, gas and the like.

Sectional view of a mechanical pipe joint according to the present invention Partial sectional view of the retaining member of FIG. Front view of the retaining member of FIG. Partial sectional view of the mechanical pipe joint of FIG. 1 showing the state before the cap nut is tightened The fragmentary sectional view which shows other embodiment of the mechanical type pipe joint by this invention Sectional drawing which shows other embodiment of the retaining member of FIG. Enlarged sectional view of the retaining member of FIG.

Explanation of symbols

  (1) ・ ・ Fitting body, (1a) ・ ・ Outer peripheral surface, (1c) ・ ・ End, (2) ・ ・ Cap nut, (2b) ・ ・ Inner peripheral surface, (3) ・ Seal member, ( 5) ・ ・ Retaining member, (6) ・ ・ Connecting pipe, (6a) ・ ・ Outer peripheral surface, (11) ・ ・ Main body screw, (12) ・ ・ Nut screw, (13) ・ Taper surface, (15) ・ ・ Sphere, (15b) ・ ・ Inner peripheral exposed part, (16) ・ ・ Holder, (16a) ・ ・ Outer peripheral surface, (16b) ・ ・ Inner peripheral surface, (17) ・ ・ Claw part, (19) ・ ・ Inclined surface, (20) ・ ・ Notch,

Claims (4)

A joint body having a main body threaded portion at the end, a cap nut having a tapered surface formed with a nut threaded portion that is screwed into the main body threaded portion of the joint body and having a diameter that increases in the direction of insertion of the connecting pipe; A seal member disposed inside the main body and in contact with the outer peripheral surface of the connecting pipe and a retaining member disposed inside the cap nut in contact with the tapered surface, when the cap nut is tightened into the joint main body In the mechanical pipe joint that presses the retaining member against the outer peripheral surface of the connecting pipe by the tapered surface of the cap nut, and prevents the connecting pipe from coming out of the joint body,
The retaining member includes a sphere that is pressed against the outer peripheral surface of the connecting pipe when the cap nut is tightened into the main body screw portion, and an annular holding member that is disposed along the tapered surface of the cap nut and holds the sphere. Prepared,
A mechanical pipe joint characterized in that a claw portion protruding toward the outer peripheral surface of the connecting pipe is provided on the inner peripheral surface of the holding body. The holding body has an inclined surface inclined along the tapered surface of the cap nut on the outer peripheral surface,
The mechanical pipe joint according to claim 1, wherein the tapered surface of the cap nut abuts against the inclined surface of the holding body to press the holding body.   3. The mechanical pipe joint according to claim 1, wherein the claw portion is formed annularly or intermittently continuously in the circumferential direction on the inner peripheral surface of the holding body. The holding body has a notch,
The mechanical pipe joint according to any one of claims 1 to 3, wherein when the retaining member is pressed by the tapered surface of the cap nut, the notch portion of the holding body is closed to reduce the outer peripheral surface of the holding body. .

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