JP5462042B2 - Fitting - Google Patents

Description

  The present invention relates to a joint used in, for example, a water supply system or a hot water supply system piping system, and more specifically, suppresses a relative movement with time between a joint body and a connecting cylinder into which a resin pipe is inserted, and has bending resistance and pullout resistance. It is related with the coupling which can improve.

  Conventionally, in a water supply system or hot water supply system, a so-called one-push type joint is known in which a resin pipe can be connected by simply inserting it, and the inserted resin pipe is retained by a retaining mechanism. Yes. As this type of joint, for example, the following joint is known (see Patent Document 1). That is, the joint has a cap mounted so that a pipe holding ring is built in the joint base. Specifically, an inner cylinder is formed on the joint base, and an outer cylinder is formed so as to cover the inner cylinder. Is fixed, a pipe holding ring is fitted into the tip of the outer cylinder, and a cap is attached.

JP 2006-329225 A

  Synthetic resins are generally used as joint materials because they are easier and cheaper to mold and handle than metals. However, in the joint described in Patent Document 1, it is considered that the joint base, the inner cylinder, the outer cylinder, and the cap are formed of resin, and between the inner cylinder and the outer cylinder and between the outer cylinder and the cap. Are connected by fitting based on unevenness. In this case, since each member formed of resin deteriorates with time and contracts or deforms, between the inner cylinder and the outer cylinder and between the outer cylinder and the cap that are connected to each other. There is a gap. As a result, there has been a problem that rattling occurs in the joint, and further bending resistance performance and pullout resistance performance are deteriorated.

  Accordingly, an object of the present invention is to reduce the rattling of the connecting portion connected by fitting in a resin joint having a retaining mechanism, and to improve the bending resistance and the pulling resistance. It is in providing the coupling which can be made.

  In order to achieve the above object, the joint according to claim 1 is provided with a coupling cylinder formed of a transparent resin fitted to the inner periphery of the end of the cylindrical coupling body, and provided in the coupling body. The engaging concave part is engaged with the engaging convex part of the connecting cylinder to form a connecting part, and the connecting cylinder has an insertion space into which the pipe is inserted. A retaining mechanism for retaining the inserted pipe is provided, and a protrusion bulging in the radial direction of the joint body is provided on the distal end side of the engaging convex portion of the connecting cylinder.

The joint according to claim 2 is characterized in that, in the invention according to claim 1, the height of the protrusion in the radial direction of the joint body is set lower than the height of the engaging convex portion.
According to a third aspect of the present invention, in the invention according to the second aspect, the interval between the protrusion in the axial direction of the joint main body and the engagement convex portion is an engagement convex portion when the connecting cylinder is inserted into the joint main body. When the is in contact with the end of the joint body, the projection is set so as to be positioned in the engagement recess.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the protrusion has a corner portion on the proximal end side of the top portion that is pressed against the inner peripheral surface of the joint body. It is characterized by that.

The joint according to claim 5 is characterized in that, in the invention according to any one of claims 1 to 4, the protrusion is a flat surface at a top portion pressed against the inner peripheral surface of the joint body. To do.
The joint according to claim 6 is the invention according to any one of claims 1 to 5, wherein the joint body is connected to the outer peripheral surface of the end of the joint body in a state where the connection cylinder is connected to the joint body. A retaining ring that holds the connection between the coupling cylinder and the retaining ring is mounted, and a latching claw that is bent at the end of the retaining ring is latched by a latching step formed in the end of the joint body. It is characterized by.

  According to a seventh aspect of the present invention, in the invention according to the sixth aspect, the retaining ring covers the outer peripheral portions of both the engaging convex portion and the protrusion in a state where the connecting cylindrical body is connected to the joint main body. It is mounted.

  In the joint according to the present invention, a coupling cylinder formed of a transparent resin is fitted to the inner periphery of the end of the coupling body, and the coupling protrusion of the coupling cylinder is engaged with the engagement recess of the coupling body. In addition, a protrusion is provided on the distal end side of the coupling convex portion of the connecting cylinder, and the protrusion bulges in the radial direction of the joint body. For this reason, when the connecting cylinder is fitted into the joint main body and the engaging convex portion is engaged with the engaging concave portion, the protrusion is pressed against the inner peripheral surface of the joint main body. Therefore, even if the resin forming the joint body and the connecting cylinder deteriorates over time and contracts or deforms, the relative movement between the joint body and the connecting cylinder is restricted, and the function of the connecting portion is maintained. Is done.

  Therefore, according to the joint of the present invention, it is possible to suppress the rattling of the connecting portion connected by fitting, and to improve the bending resistance and the pulling resistance.

The half longitudinal cross-sectional view which shows the coupling in 1st Embodiment of this invention. Sectional drawing which expands and shows the connection part of a coupling. It is a figure which shows the effect | action of a coupling | joint, Comprising: The partial expanded sectional view which shows the state which the engagement convex part of the connection cylinder contacted the edge part inner periphery of the coupling main body. The partial expanded sectional view which shows the state which inserted the connection cylinder further in the coupling main body from the state of FIG. Sectional drawing in the 5-5 line | wire of FIG. The partial expanded sectional view which shows the effect | action of a coupling | joint and shows the state which mounts a holding | maintenance ring in the state with which the coupling cylinder was connected with the coupling main body. The partial expanded sectional view which shows the state which inserts the resin pipe in the insertion space of a coupling. The longitudinal cross-sectional view which shows the coupling in 2nd Embodiment of this invention. Sectional drawing which expands and shows the connection part of a coupling.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.
As shown in FIGS. 1 and 5, the joint body 11 constituting the joint 10 is formed in a substantially cylindrical shape by a synthetic resin containing rubber such as polyphenylene sulfide (PPS) mixed with rubber, and is formed in both outer end portions. Each of the peripheral surfaces is provided with an annular engaging recess 12. A pair of connecting cylinders 13 are fitted to both ends of the joint body 11, and the engaging projections 14 provided on the outer peripheral surfaces of the inner ends are engaged with the engaging recesses 12 of the joint body 11. It is connected and the connection part is comprised.

  As shown in FIG. 2, an annular protrusion 52 having an annular shape as a protrusion that bulges in the radial direction y of the joint main body 11 is provided on the outer peripheral surface of the inner end portion of both the connecting cylinders 13. It is designed to be pressed against the peripheral surface. The annular ridge 52 is formed in a trapezoidal cross section, and the top portion thereof is a flat surface 53 and has a corner portion 54 perpendicular to the cross section on the base end side of the top portion. Furthermore, the front end surface of the annular protrusion 52 is an inclined surface 55, and the rear end surface is a vertical surface 56 extending in the radial direction y of the joint body 11. In the state where the connecting cylinder 13 is assembled to the joint body 11, the annular protrusion 52 is pressed against the inner peripheral surface of the joint body 11, thereby preventing a gap from being generated in the connecting portion, and the axis of the joint body 11. Resistance to the pulling force outward in the direction x can be expressed, and resistance to bending stress can be expressed.

  The height of the annular protrusion 52 in the radial direction y is set to be lower than the height of the engaging projection 14, and the sliding contact resistance of the annular protrusion 52 with respect to the inner peripheral surface of the joint body 11 is suppressed, so 13 is easy to insert. The height of the annular protrusion 52 is set to be large in advance in consideration of shrinkage due to deterioration (thermal deterioration) of the resin forming the connecting cylinder 13 and the joint body 11. The interval between the annular protrusion 52 and the engaging protrusion 14 in the axial direction x is such that the engaging protrusion 14 contacts the end of the joint body 11 when the connecting cylinder 13 is inserted into the joint body 11. The annular protrusion 52 is set so as to be positioned in the engagement recess 12 (see FIG. 3). In this case, the sliding contact resistance of the annular protrusion 52 with respect to the inner peripheral surface of the joint body 11 can be suppressed when the connection cylinder 13 is inserted, and the connection cylinder 13 can be easily inserted.

  As shown in FIG. 1, a support receiving surface 18 for supporting the retaining ring 17 is recessed on the outer peripheral surface of the joint body 11 on both outer end sides, and a contact surface due to an engagement step is formed on the inner end portion thereof. 19 is provided, and a locking step 20 is cut out at the outer end. A cylindrical holding ring 17 is fitted on the support receiving surface 18, and its inner end is in contact with the contact surface 19 of the joint body 11 and is bent toward the inner peripheral side of the outer end. The locking claw 21 is locked to the locking step 20. The holding ring 17 is configured to hold the connection of the connecting portion between the joint body 11 and the connecting cylinder 13.

  As shown in FIGS. 1 and 5, the connecting cylinder 13 is formed in a hexagonal cylinder (regular hexagonal cylinder) with a transparent resin such as an amorphous nylon resin (amorphous polyamide resin), and the inside is seen through. It is configured to be able to. The connecting cylinder 13 may be in the form of a rectangular cylinder, and may be in the shape of a square cylinder, an octagonal cylinder, or the like. A ridgeline portion 22 extending in the axial direction x is provided at six locations in the circumferential direction of the outer peripheral portion of the connecting cylinder 13, and the retaining ring 17, particularly the locking claw 21, slides on the ridgeline portion 22. . The top portion of the ridge line portion 22 is chamfered to become a chamfered portion 22a so that the locking claw 21 of the holding ring 17 can easily slide.

  The ridge line portion 22 is configured such that the outer end 22b side is lower than the inner end 22c side, so as to reduce the sliding resistance when the retaining claw 21 of the retaining ring 17 slides on the outer end 22b. It is configured. An inclined surface 22d is formed between the outer end 22b and the inner end 22c of the ridge line portion 22, and the holding ring 17 is configured to ride on the inner end 22c from the outer end 22b of the ridge line portion 22 through the inclined surface 22d. Yes. The inner end 22 c of the ridge line portion 22 is locked to the locking claw 21 of the holding ring 17 supported on the support receiving surface 18. The outer surface other than the ridge line portion 22 of the connecting cylinder 13 is a smooth surface 51, and the inside can be seen through from the smooth surface 51. A holding groove 23 is formed by the locking step portion 20 of the joint body 11 and the inner end 22c of the ridge line portion 22 of the connecting cylinder 13, and the locking claw 21 of the holding ring 17 enters the holding groove 23 to prevent it from coming off. It is supposed to be retained.

  Insert members 24 formed of stainless steel (SUS304, SUS316, etc.), bronze, aluminum or the like are inserted into the joint body 11 from both outer ends of the joint body 11, and bent pieces 24a at both inner ends. Is in contact with the annular wall 25 projecting toward the inner peripheral side of the joint body 11. The insert member 24 is formed in a cylindrical shape by punching a metal plate material by press drawing. The insert member 24 has a plurality of step portions 26 that are reduced in diameter from the inner end side toward the outer end side when mounted in the joint body 11. The step portion 26 includes a first step portion 26a, a second step portion 26b, a third step portion 26c, and a fourth step portion 26d from the inner end side. Four engagement holes 27 are formed in the circumferential direction in the substantially central portion of the fourth step portion 26d at intervals of 90 degrees in the circumferential direction.

  An insertion space 29 into which the resin pipe 28 is inserted is formed between the inner peripheral surface of the connecting cylinder 13 and the outer peripheral surface of the insert member 24. A seal ring 30 formed of rubber such as ethylene-propylene-diene copolymer rubber (EPDM) is fitted between the first step portion 26 a of the insert member 24 and the joint body 11. The sealability between the end portion and the inner peripheral surface of the joint body 11 is ensured. The resin pipe 28 is formed of a synthetic resin such as polyolefin (crosslinked polyethylene, polybutene, etc.). The inner space of the insert member 24 is a flow hole 31 through which a fluid such as water flows.

  On the second step portion 26 b of the insert member 24, a pressing member 32 that presses the seal ring 30 is interposed between the joint body 11 and the connecting cylinder 13. The pressing member 32 is formed with a thick central portion in the radial direction to form a thick portion 33, and the seal ring 30 is pressed by the inner end surface of the thick portion 33. On the inner peripheral surface of the presser member 32, four bulging portions 34 are provided in the circumferential direction at every 90 degrees, and the presser member 32 is pressure-bonded to the outer peripheral surface of the insert member 24 in a state where the insert member 24 is inserted. The

  A sealing material 35 having a flat corrugated shape is fitted at a position straddling the third step portion 26 c and the fourth step portion 26 d of the insert member 24. A restricting member 36 is attached to the outer periphery of the opening end portion of the insert member 24 to prevent the sealing material 35 from coming off. An engaging projection (not shown) that engages with the engaging hole 27 of the insert member 24 is provided on the inner peripheral surface of the restricting member 36, and the restricting member 36 is fixed to the insert member 24. A stopper portion 37 that is engaged with the outer end portion of the insert member 24 is formed on the inner peripheral surface of the outer end side of the regulating member 36 so as to protrude.

  A male screw 40 is threaded on the outer peripheral surface on the outer end side of the connecting cylinder 13, a female screw 43 of a cap (clamping nut) 41 made of glass fiber reinforced nylon resin is screwed, and the cap 41 is connected to the connecting cylinder 13. To be connected to. A retaining ring 44 that is made of a metal such as stainless steel and prevents the resin pipe 28 from being interposed is interposed between the outer end surface of the connecting cylinder 13 and the inner peripheral surface (inner end surface) of the cap 41. A retaining piece 44a is formed on the inner peripheral portion of the retaining ring 44 so as to project in an oblique direction so as to bite into the outer peripheral portion of the resin pipe 28 and prevent the resin pipe 28 from coming off.

  A split ring 46 is interposed between the retaining ring 44 and the inclined surface 45 on the inner periphery of the cap 41, and is configured to maintain the inclination angle of the retaining piece 44a. An inclined surface 47 having the same inclination angle as the inclined surface 45 of the cap 41 is provided at the outer end portion of the split ring 46, and the split ring 46 is interposed via a retaining piece 44 a by a force in the drawing direction of the resin pipe 28. When receiving a force in the axial direction x, the split ring 46 is configured to be reduced in diameter. A tightening surface 48 formed on the inner peripheral surface of the split ring 46 tightens the resin pipe 28. The above-described retaining ring 44, split ring 46, cap 41 and the like constitute a retaining mechanism for the resin pipe 28.

  In the insertion space 29 of the resin pipe 28, an insertion guide 49 that is pressed against the front end surface of the resin pipe 28 to guide insertion of the resin pipe 28 is disposed. The insertion guide 49 is formed in a C-ring shape and is configured to be able to expand and contract. An engagement step 50 is provided on the inner peripheral surface of the split ring 46, and the outer peripheral portion of the outer end surface of the insertion guide 49 is engaged with the engagement step 50, so that the insertion guide 49 is retained.

As described above, the joint 10 includes the joint main body 11 having the engagement concave portion 12, the connection cylindrical body 13 having the engagement convex portion 14 and the annular protrusion 52, the holding ring 17, and a retaining mechanism.
Next, the effect | action is demonstrated about the coupling 10 comprised as mentioned above.

  Now, as shown in FIG. 3, when connecting the connecting cylinder 13 to the joint body 11, if the inner end of the connecting cylinder 13 is inserted into the inner periphery of the end of the joint body 11, The mating convex portion 14 is in sliding contact with the tapered surface 11 a on the inner periphery of the end portion of the joint body 11. At this time, the annular protrusion 52 of the connecting cylinder 13 is located in the engagement recess 12 of the joint body 11. When the connecting cylinder 13 is further inserted into the joint body 11, the engaging convex part 14 advances while expanding the end of the joint body 11 as shown in FIG. 4. At the same time, the annular protrusion 52 advances while being gradually pressed strongly against the inner peripheral surface of the joint body 11.

  As shown in FIG. 2, when the connecting cylinder 13 is further inserted into the joint body 11 and the engagement convex portion 14 engages with the engagement concave portion 12, the end of the joint body 11 is reduced in diameter to the original position. Restore to. At this time, the annular protrusion 52 is pressed against the inner peripheral surface of the joint main body 11, and the top part slightly bites into the inner peripheral surface of the joint main body 11. Therefore, the relative movement between the connecting cylinder 13 and the joint body 11 is restricted. Further, for example, when a pulling force acting on the resin pipe 28 is applied to the connecting cylinder 13 through the retaining mechanism and the cap 41, the corner portion 54 at the top of the annular protrusion 52 is formed on the inner peripheral portion of the joint body 11. You can bite and stand on it. In addition, for example, when a bending stress in the radial direction y acting on the resin pipe 28 is applied to the connecting cylinder 13, the flat surface 53 at the top of the annular protrusion 52 presses the inner peripheral surface of the joint body 11. Resistance to bending stress can be expressed.

  Subsequently, as shown in FIG. 6, after engaging the engaging convex portion 14 with the engaging concave portion 12, the holding ring 17 is inserted from the outer end side of the connecting cylindrical body 13, and the inner end portion thereof is the joint body 11. So as to be positioned on the support receiving surface 18. At this time, since the connecting cylinder 13 is formed in a hexagonal cylinder shape, the locking claw 21 of the holding ring 17 slides on the ridge line portion 22 of the connecting cylinder 13. Therefore, the smooth surface 51 of the connecting cylinder 13 can be prevented from being damaged, and the inside can be satisfactorily seen through the smooth surface 51.

  As shown in FIG. 7, when the holding ring 17 is further inserted, the inner end of the retaining ring 17 comes into contact with the contact surface 19 of the joint body 11, and the outer end engages with the locking step portion 20 of the joint body 11. Stopped. Thereafter, when the resin pipe 28 is inserted into the insertion space 29, the inner end of the resin pipe 28 is guided and inserted by the insertion guide 49, and the inner end portion of the insertion guide 49 abuts against the presser member 32. In this way, as shown in FIG. 1, the two resin pipes 28 are connected to both ends of the joint 10.

The effects exhibited by the above first embodiment will be described collectively below.
(1) In the joint 10 of the present embodiment, the engagement convex portion 14 of the coupling cylinder 13 is engaged with the engagement concave portion 12 on the inner periphery of the end portion of the joint main body 11 to form the coupling portion, and the engagement convexity An annular ridge 52 that bulges in the radial direction y is provided on the tip side of the portion 14. For this reason, when the connecting cylinder 13 is fitted into the joint main body 11 and the engaging convex portion 14 is engaged with the engaging concave portion 12, the annular protrusion 52 is pressed against the inner peripheral surface of the joint main body 11. Therefore, even if the resin forming the joint body 11 and the connecting cylinder 13 deteriorates with time and contracts or deforms, the joint body 11 and the connecting cylinder 13 do not move relative to each other, and the function of the connecting portion is maintained. Is done.

  Therefore, according to the joint 10 of 1st Embodiment, after using it for a long time, while being able to suppress the rattling of the connection part connected by fitting, it can improve a bending-proof performance and a pull-out-proof performance. it can.

  (2) Since the height of the annular protrusion 52 in the radial direction y of the joint body 11 is set lower than the height of the engaging projection 14, the sliding resistance of the connecting cylinder 13 against the inner peripheral surface of the joint body 11 Therefore, the connecting cylinder 13 can be smoothly inserted into the joint body 11.

  (3) The interval between the annular protrusion 52 and the engagement protrusion 14 in the axial direction x of the joint body 11 is such that the engagement protrusion 14 is connected to the end of the joint body 11 when the connecting cylinder 13 is inserted into the joint body 11. The annular protrusion 52 is set so as to be positioned in the engagement recess 12 when it comes into contact with the tapered surface 11a on the inner periphery of the part. For this reason, it is possible to suppress an increase in sliding resistance caused by the annular protrusion 52 pressing the inner peripheral surface of the joint body 11 when the connection cylinder 13 is inserted, and the connection cylinder 13 into the joint body 11 can be suppressed. Insertion can be performed more smoothly.

  (4) The annular protrusion 52 has a corner portion 54 on the proximal end side of the top portion pressed against the inner peripheral surface of the joint body 11, so that the connection cylinder after the connection cylinder body 13 is connected to the joint body 11. When the body 13 receives the pulling force outward in the axial direction x, the top corners 54 bite into the inner periphery of the joint body 11. For this reason, the connection of the connection part of the connection cylinder 13 with respect to the joint main body 11 becomes strong, the axial direction x can be received sufficiently, and the pull-out resistance of the joint 10 can be improved. .

  (5) Since the top of the annular ridge 52 that is in pressure contact with the inner peripheral surface of the joint body is the flat surface 53, the area of the top of the annular ridge 52 that is in pressure contact with the inner peripheral surface of the joint main body 11 is increased. Is done. For this reason, when the connecting cylinder 13 is subjected to a bending stress in the radial direction y after the connecting cylinder 13 is connected to the joint body 11, the bending stress can be received by a large area of the flat surface 53 of the annular protrusion 52. The bending resistance performance of the joint 10 can be improved.

  (6) A retaining ring 17 that holds the connection between the joint body 11 and the connection cylinder 13 is mounted on the outer peripheral surface of the end of the joint body 11 in a state where the connection cylinder 13 is connected to the joint body 11, A locking claw 21 that is bent at the outer end of the ring 17 is locked to a locking step 20 that is notched at the end of the joint body 11. For this reason, the connection of the connection part of the coupling main body 11 and the connection cylinder 13 can be hold | maintained firmly.

(7) The holding ring 17 is mounted so as to cover the outer peripheral portions of both the engaging protrusion 14 and the annular protrusion 52 in a state where the connecting cylinder 13 is connected to the joint body 11. For this reason, while being able to hold | maintain the connection of the connection part of the coupling main body 11 and the connection cylinder 13 still more firmly, suppression of rattling based on the cyclic | annular protrusion 52 can be performed effectively, and bending resistance performance In addition, the pull-out resistance can be effectively exhibited.
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, parts different from the first embodiment will be mainly described.

  As shown in FIGS. 8 and 9, in the second embodiment, instead of the insert member 24, inner cylindrical portions 57 are formed to project from the inner circumferences of both ends of the joint body 11. A pair of annular grooves 58 are recessed in the outer peripheral surface of each inner cylinder portion 57, and a sealing member 59 is fitted to maintain the sealing performance between the inner cylinder portion 57 and the resin pipe 28. Note that the seal ring 30, the pressing member 32, the regulating member 36, and the like are not provided.

  As shown in FIG. 9, an annular annular ridge 52 a is provided on the outer peripheral surface of the distal end from the engaging convex portion 14 of the connecting cylinder 13. The annular protrusion 52a is formed in a circular arc shape in cross section, and its height in the radial direction y is set to be lower than the height of the engaging projection 14. Further, the interval between the annular protrusion 52a and the engaging protrusion 14 in the axial direction x is such that the engaging protrusion 14 is in contact with the tapered surface 11a at the end of the joint body 11 when the connecting cylinder 13 is inserted into the joint body 11. The annular protrusion 52a is set so as to be positioned in the engaging recess 12 when contacted.

  Therefore, in the second embodiment, since the annular ridge 52a is formed in an arcuate cross section, the annular ridge 52a with respect to the inner peripheral surface of the joint body 11 is inserted when the connecting cylinder 13 is inserted into the joint body 11. The slidability is good, and the connecting cylinder 13 can be inserted smoothly. Further, the joint 10 is not provided with the insert member 24, the seal ring 30, the pressing member 32, the regulating member 36, and the like, and an annular groove 58 is provided in the inner cylinder portion 57 integrally formed with the joint body 11 for sealing. Since the configuration in which the member 59 is fitted is employed, the configuration of the joint 10 can be simplified.

It should be noted that both the above embodiments can be modified and embodied as follows.
The annular ridge 52a of the second embodiment can be provided instead of the annular ridge 52 of the first embodiment, and the annular ridge 52 of the first embodiment can be replaced with the annular ridge 52a of the second embodiment. Can be provided.

-The annular protrusions 52 and 52a of both embodiments can also be formed in shapes, such as a cross-sectional triangle shape and a cross-sectional pentagon shape.
-It is also possible to provide a plurality of annular ridges 52, 52a of both embodiments. In that case, the interval between the annular ridges 52, 52a, the height of each annular ridge 52, 52a, the area of the flat surface 53, and the like can be appropriately set according to the purpose.

  -Instead of the annular ridges 52, 52a of both embodiments, it is also possible to provide protrusions at a plurality of locations, for example, at four locations at intervals of 90 degrees in the circumferential direction and at six locations at intervals of 60 degrees in the circumferential direction. It is.

  The joint body 11 or the like can be formed of a synthetic resin (engineering plastic) such as polyacetal (POM), polyphthalamide (PPA), or polyphenylsulfone (PPSU). Further, the connecting cylinder 13 can be formed of a synthetic resin such as polycarbonate, PPSU, PES (polyethersulfone), PSU (polysulfone), which is a transparent resin.

  In the embodiment, the joint body 10 is embodied in the type of the joint 10 in which the resin pipe 28 is connected to both ends of the joint body 11, but the resin pipe 28 is connected to one end portion of the joint body 11, and the other end portion is connected to the faucet fitting. It can also be embodied in the type of joint 10.

As the pipe, a soft metal pipe such as a copper pipe can be used in addition to the resin pipe 28.
The joint 10 can be used for connecting a water heating system pipe, a hot water system pipe, a floor heating pipe, a road heating pipe, and the like.

Further, the technical idea that can be grasped from the embodiment will be described below.
(B) The joint body according to any one of claims 1 to 6, wherein the joint body is made of a resin containing rubber. When comprised in this way, in addition to the effect of the invention which concerns on any one of Claims 1-6, while inserting the connection cylinder body in a coupling main body can be performed smoothly, a coupling main body internal peripheral surface It is possible to improve the biting performance of the projections of the connecting cylinders to improve the bending resistance and pull-out performance of the joint.

  (B) The joint according to any one of claims 1 to 6, wherein the connecting cylinder is made of an amorphous polyamide resin. When constituted in this way, in addition to the effect of the invention according to any one of claims 1 to 6, it is possible to suppress the shrinkage of the projections of the connecting cylindrical body, and to further improve the bending resistance and pull-out resistance of the joint. Can be improved.

  DESCRIPTION OF SYMBOLS 10 ... Joint, 11 ... Joint main body, 12 ... Engagement recessed part which comprises a connection part, 13 ... Connection cylinder, 14 ... Engagement convex part which comprises a connection part, 17 ... Holding ring, 20 ... Locking step part, DESCRIPTION OF SYMBOLS 21 ... Locking claw, 28 ... Resin pipe, 29 ... Insertion space, 44 ... Retaining ring which comprises a retaining mechanism, 52, 52a ... An annular protrusion as a protrusion, 53 ... Flat surface, 54 ... Corner | angular part, x: axial direction, y: radial direction.

Claims (7)

A connecting cylinder formed of a transparent resin is fitted to the inner periphery of the end portion of the joint body having a cylindrical shape, and an engaging convex portion of the connecting cylinder is engaged with an engaging recess provided in the joint body. A connecting portion is formed, the connecting cylinder has an insertion space into which the pipe is inserted, and an outer end portion of the connecting cylinder has a retaining mechanism for retaining the inserted pipe.
A joint comprising a protrusion bulging in a radial direction of the joint main body on a distal end side of the engagement convex portion of the connecting cylinder. The joint according to claim 1, wherein the height of the protrusion in the radial direction of the joint body is set to be lower than the height of the engaging protrusion. The distance between the protrusion in the axial direction of the joint body and the engagement protrusion is such that when the engagement protrusion comes into contact with the end of the joint body when the connecting cylinder is inserted into the joint body, the protrusion is in the engagement recess. The joint according to claim 2, wherein the joint is set so as to be positioned at the position. The joint according to any one of claims 1 to 3, wherein the protrusion has a corner portion on a proximal end side of a top portion pressed against an inner peripheral surface of the joint main body. The joint according to any one of claims 1 to 4, wherein the projection has a flat surface at a top portion pressed against the inner peripheral surface of the joint body. A holding ring that holds the connection between the joint body and the connecting cylinder is mounted on the outer peripheral surface of the end of the joint body in a state where the connecting cylinder is connected to the joint body, and is bent at the end of the holding ring. The joint according to any one of claims 1 to 5, wherein the latching claw is latched by a latching step portion formed by cutting out at an end portion of the joint body. The joint according to claim 6, wherein the holding ring is mounted so as to cover the outer peripheral portions of both the engaging convex portion and the protrusion in a state where the connecting cylindrical body is connected to the joint main body.

Images