JP2013155878A - Spigot type pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spigot type pipe joint capable of preventing a packing from being pushed out from a packing fitting groove on an end face of a connecting pipe, and besides capable of preventing biting of dust and foreign matter between an inner peripheral face of the connecting pipe and a sealing portion of the packing, damage to the sealing portion, and degradation of seal performance.SOLUTION: Packing 4 for sealing a portion between an inner periphery of an end of a connecting pipe P and an outer periphery of an inner cylinder 2 is fitted to a packing fitting groove 14 formed in an outer peripheral face of the inner cylinder 2. A groove sidewall 14b of the packing fitting groove 14 on a downstream side in an insertion direction of the connecting pipe P is formed as a vertical wall with respect to a bottom of the packing fitting groove 14. An end on the side of a groove opening of the groove sidewall 14b is formed to be positioned closer to the outside in a radial direction of the inner cylinder 2 than an end on the side of an outer periphery of an end face wall 4f of the packing 4 on the downstream side in the insertion direction of the connecting pipe P. An end face of the packing 4 on the downstream side in the insertion direction of the connecting pipe is formed in a tapered manner into a shape gradually narrowed toward the downstream side in the insertion direction of the connecting pipe.

Description

  The present invention relates to a plug-in type fitting that is used for hot water supply / water supply piping, etc., and can be connected in a seal shape by simply inserting a connecting pipe, and more specifically, when a connecting pipe is inserted, a packing fitting in the pipe fitting is fitted. The present invention relates to an improvement of a plug-in type pipe joint that can prevent a packing fitted in a groove from being pushed out from a packing fitting groove at an end face of a connecting pipe.

  As this kind of plug-in type pipe joint, for example, those shown in FIGS. 15 to 17 are known (for example, see Patent Document 1). The plug-in type pipe joint is provided with an inner cylinder 31 into which the end of the connecting pipe P is inserted into an outer fitting shape inside the joint body 30, and an annular packing fitting groove 32 is provided on the outer periphery of the inner cylinder 31. The packing 33 for sealing between the inner periphery of the end of the connecting pipe P and the outer periphery of the inner cylinder 31 is fitted in the packing fitting groove 32. The packing 33 is formed with a protruding portion 33 a that protrudes radially outward from the outer peripheral surface of the inner cylinder 31. Further, the packing 33 is provided with a flat portion 33b having an outer peripheral surface formed substantially flush with the outer peripheral surface of the inner cylinder 31 at a position upstream of the protruding portion 33a in the insertion direction of the connecting pipe P. Yes.

  In such a plug-in type pipe joint, when the connecting pipe P is inserted, when the end of the connecting pipe P passes through the packing 33, first, the flat portion 33b located upstream of the packing 33 in the inserting direction of the connecting pipe P is formed. After first fitting in the connecting pipe P, the protruding portion 33a is subsequently fitted. For this reason, when the end surface of the connecting pipe P abuts against the protruding portion 33 a of the packing 33, the flat portion 33 b of the packing 33 is already fitted into the connecting pipe P. In the packing 33 in which the flat portion 33b is fitted in the connecting pipe P, the movement in the axial direction is restricted to some extent because the flat portion 33b is pressed from the radially outer side and pressed against the packing fitting groove 32. It is in the state that was done. Therefore, even if the connecting pipe P is further pushed in from the state where it abuts against the protruding portion 33a of the packing 33, there is little possibility that the packing 33 will be pushed out of the packing fitting groove 32 by being pushed by the connecting pipe P. .

JP 2003-42370 A

  By the way, cutting scraps and other dust and foreign matters on the connection pipe P are often attached to the inner peripheral surface of the connection pipe P. When the connection pipe P is directly fitted on the inner cylinder 31, the flat portion 33b of the packing 33 Since the outer peripheral surface is substantially flush with the outer peripheral surface of the inner cylinder 31, it is hardly expected that the flat portion 33 b removes dust and foreign matters. The dust and foreign matters are not in contact with the inner peripheral surface of the connecting pipe P and the packing. There is a problem that the projection 33a is bitten between the projection 33a and the projection 33a is damaged or the seal performance is deteriorated.

  The present invention has been made in order to solve such a problem, and the object of the present invention is to provide an internal fitting body in which the end of the connecting pipe is inserted into an outer fitting shape as described above. An annular packing fitting groove is provided on the outer peripheral surface of the inner cylinder, and a packing for sealing between the inner periphery of the end of the connecting tube and the outer periphery of the inner cylinder is fitted in the packing fitting groove. In the plug-in type fittings that fit together, the gasket can be prevented from being pushed out from the packing fitting groove on the end face of the connecting pipe by devising the cross-sectional shape of the packing, and the inner peripheral surface of the connecting pipe and the seal of the packing It is an object of the present invention to provide a plug-in type pipe joint that can prevent dust and foreign matter from being caught between parts, damage to a seal part, and deterioration of seal performance.

  The plug-in type pipe joint according to the present invention will be described with reference to the reference numerals attached to FIGS. 1 to 14 in order to facilitate understanding of the contents of the invention. The inner tube 2 into which the end portion of the connecting pipe P is inserted into an outer fitting shape is provided, and an annular packing fitting groove 14 is provided on the outer peripheral surface of the inner tube 2, and the connecting pipe P is inserted into the packing fitting groove 14. In the plug-in type pipe joint in which the packing 4 for sealing between the inner periphery of the end of the inner tube 2 and the outer periphery of the inner cylinder 2 is fitted, the packing 4 is in a state of being fitted in the packing fitting groove 14. A seal portion 4 a that protrudes radially outward from the outer peripheral surface of the inner cylinder 2 is formed, and the inner cylinder 2 is positioned at a position corresponding to the upstream side in the insertion direction of the connecting pipe P with respect to the seal portion 4 a in the packing 4. A dust removal cleaning portion 4b that protrudes radially outward from the outer peripheral surface is formed. The groove side wall 14b on the downstream side in the insertion direction of the connecting pipe P in the fitting groove 14 is formed in a vertical wall with respect to the bottom of the packing fitting groove 14, and the groove opening side end of the groove side wall 14b is connected in the packing 4. The pipe P is formed so as to be positioned on the radially outer side of the inner cylinder 2 with respect to the outer peripheral side end portion of the end face wall 4f on the downstream side in the insertion direction of the pipe P. It is characterized in that the taper is gradually tapered toward the downstream side in the insertion direction.

  According to the packing having the above-described configuration, when the connecting pipe P is inserted, when the end of the connecting pipe P passes through the packing 4, first, the dust removal cleaning unit 4 b located upstream of the packing 4 in the inserting direction of the connecting pipe P is first. Then, the seal portion 4a is fitted into the connecting pipe P. For this reason, when the end surface of the connecting pipe P hits the seal part 4a of the packing 4, the dust removal cleaning part 4b of the packing 4 is already fitted in the connecting pipe P. In the packing 4 in which the dust removal cleaning part 4b is fitted in the connecting pipe P, the dust removal cleaning part 4b is pressed radially inward on the inner peripheral surface of the connection pipe P and pressed against the packing fitting groove 14. Therefore, the movement in the axial direction is regulated to some extent. Therefore, even if the connecting pipe P is pushed deeper from the state where the end surface of the connecting pipe P abuts against the seal portion 4 a of the packing 4, it is possible to prevent the packing 4 from being pushed out of the packing fitting groove 14 by the connecting pipe P.

  In addition, when the connecting pipe P is inserted, first, the dust removal cleaning portion 4b of the packing 4 protruding radially outward from the outer peripheral surface of the inner cylinder 2 is first fitted into the connecting pipe P so that the inner surface of the connecting pipe P is inserted. The dust and foreign matter adhering to the inner surface of the connecting pipe P are surely removed by the dust removing cleaning part 4b, and the dust and foreign substances are removed between the inner peripheral surface of the connecting pipe P and the seal part 4a of the packing 4. It is possible to prevent the seal portion 4a from being scratched or the sealing performance from being lowered.

  In addition, the downstream end wall 4f in the insertion direction of the connecting pipe P of the packing 4 abuts against the groove side wall 14b and is pushed toward the bottom of the packing fitting groove 14, so that the packing 4 is removed from the packing fitting groove 14. Extrusion can be prevented more effectively.

  As described in claim 2, the plug-in type pipe joint according to claim 1 is depressed inward in the radial direction from the outer peripheral surface of the inner cylinder 2 between the seal portion 4a and the dust removal cleaning portion 4b of the packing 4. The structure which formed the annular groove 4c to perform in the circumferential direction is employable. According to this configuration, the annular concave groove 4c formed between the seal portion 4a and the dust removal cleaning portion 4b is used as a relief of the dust removal cleaning portion 4b that is pressed inward in the radial direction by the inner surface of the connecting pipe P and is compressed and deformed. Works effectively. Therefore, the dust removal cleaning part 4b can be easily compressed and deformed when pressed inward in the radial direction by the connecting pipe P, whereby dust and foreign substances can be more reliably removed by the dust removal cleaning part 4b. Further, since the same concave groove 4c functions effectively as a relief of the seal portion 4a that is pressed and deformed radially inward by the connecting pipe P, the seal portion 4a is pressed inward in the radial direction by the connecting pipe P. When it is done, it can be easily compressed and deformed, and the connecting pipe P can be easily inserted.

  As described in claim 3, the plug-in type pipe joint according to claim 1 is directed to the upstream end surface side of the connecting pipe P in the dust removal cleaning portion 4 b toward the upstream side in the inserting direction of the connecting pipe P. A configuration in which the tapered taper 15 is gradually formed can be employed. According to this configuration, when the connecting pipe P is inserted, the removal cleaning portion 4b of the packing 4 is easily fitted into the connecting pipe P.

  According to the plug-in type pipe joint of the present invention, it is possible to prevent the packing from being pushed out from the packing fitting groove at the end face of the connecting pipe, and to prevent dust and foreign matters between the inner peripheral surface of the connecting pipe and the seal portion of the packing. It is possible to prevent biting, scratching the seal portion, and lowering the sealing performance.

It is a half notched cross-sectional view showing the plug-in type pipe joint of one reference example of the present invention in a state before inserting the connecting pipe. FIG. 2 is a half-broken cross-sectional view showing the plug-in type pipe joint of FIG. 1 in a state where the connecting pipe is being inserted. FIG. 2 is a half cutaway cross-sectional view showing the plug-in type pipe joint of FIG. 1 in a state after the connection pipe is inserted. FIG. 2 is a half cutaway cross-sectional view of an inner cylinder and packing of the plug-in type pipe joint of FIG. 1. It is a half notched cross-sectional view of the packing of the plug-in type pipe joint of FIG. It is a half notched cross-sectional view of the packing of another reference example. It is a half notched cross-sectional view of the packing of still another reference example. Furthermore, it is a half notched cross-sectional view of the packing of another reference example. It is a half notched cross-sectional view of the inner cylinder and packing of a plug-in type pipe joint which shows the other reference example corresponding to FIG. It is a half notched cross-sectional view of the packing of one Example of this invention. FIG. 6 is a half cutaway cross-sectional view of an inner tube and packing of a plug-in type pipe joint according to another embodiment. Furthermore, it is a half notched cross-sectional view of the inner cylinder and packing of the plug-in type pipe joint, showing another reference example corresponding to FIG. It is a half notched cross-sectional view showing the plug-in type pipe joint of another reference example in a state before inserting the connecting pipe. FIG. 14 is a half cutaway cross-sectional view showing the plug-in type pipe joint of FIG. 13 in a state after the connection pipe is inserted. It is a half notched cross-sectional view showing the plug-in type pipe joint of the conventional example in a state before inserting the connecting pipe. It is an expanded sectional view of the packing of the insertion type pipe joint of the conventional example of FIG. FIG. 16 is a half-broken cross-sectional view showing the plug-in type pipe joint of the conventional example of FIG. 15 in a state after the connection pipe is inserted.

  Preferred embodiments and reference examples of the present invention will be described with reference to the drawings. FIG. 1 is a half-notch cross-sectional view showing the plug-in type pipe joint of the first reference example in a state before the connection pipe is inserted, and FIG. 2 is a half-notch cross-sectional view showing the plug-in type pipe joint in FIG. FIG. 3 is a half cutaway cross-sectional view showing the plug-in type pipe joint of FIG. 1 in a state after the connection pipe is inserted, FIG. 4 is a cross-sectional view of the internal cylinder and packing of the plug-in type pipe joint of FIG. 5 is a half cutaway cross-sectional view of the packing of the plug-in type pipe joint of FIG.

  In FIG. 1, the plug-in type pipe joint includes an inner cylinder 2, an outer cylinder 3, a packing 4, a retaining ring 5, and a cap 6 in a joint body 1.

  As shown in FIG. 1, the joint body 1 is formed in a cylindrical shape with a metal such as bronze casting or plastic, and has a fluid passage 7 formed in a penetrating shape in the axial direction. The inner cylinder 2 is integrally protruded from the portion outward in the axial direction in parallel with the central axis O of the fluid passage 7, and the fluid passage 7 is formed in communication with the inside of the inner cylinder 2. Further, at one end in the axial direction of the joint body 1, a connecting pipe made of resin or metal such as polybutene or cross-linked polyethylene is provided between the outer cylinder 3 formed separately from the joint body 1 and the outer peripheral surface of the inner cylinder 2. It is attached concentrically with the inner cylinder 2 so as to form a connecting pipe insertion gap 8 for receiving the end of P. At the time of attachment, the inner peripheral step portion 9 of the base end portion of the outer cylinder 3 is press-fitted into the step portion 10 formed on the outer periphery of the base portion of the inner cylinder 2 of the joint body 1 to be engaged and fixed.

  A cylindrical cap 6 is integrally attached to the opening end of the outer cylinder 3. At the time of attachment, an annular protrusion 12 provided on the inner periphery of the base end of the cap 6 is press-fitted into an annular groove 11 provided on the outer periphery of the opening end of the outer cylinder 3. It is attached concentrically with the inner cylinder 2 so as to form a connection pipe receiving port 13 communicating with the connection pipe insertion gap 8 between the outer circumference of the inner cylinder 2.

As shown in FIGS. 1 and 4, a packing fitting groove 14 is provided on the outer peripheral surface of the inner cylinder 2, and the inner circumference of the end of the connecting pipe P and the outer circumference of the inner cylinder 2 are formed in the packing fitting groove 14. A cylindrical packing 4 made of synthetic rubber, natural rubber, synthetic resin, or the like is sealed.
As shown in FIGS. 4 and 5, the packing 4 forms a seal portion 4 a that protrudes radially outward from the outer peripheral surface of the inner cylinder 2 in a state where the packing 4 is fitted in the packing fitting groove 14. Further, at a position corresponding to the upstream side (see FIG. 4) of the connecting pipe P in the insertion direction of the connecting pipe P with respect to the seal portion 4a in the packing 4, a dust removal cleaning portion 4b protruding radially outward from the outer peripheral surface of the inner cylinder 2 is provided. Forming. Between the seal part 4a and the dust removal cleaning part 4b in the packing 4, an annular concave groove 4c is formed in the circumferential direction, which is recessed radially inward from the outer peripheral surface of the inner cylinder 2.

  Further, the packing 4 will be described in detail. As shown in FIGS. 4 and 5, the upstream end surface side of the connecting pipe P in the dust removal cleaning portion 4 b is gradually narrowed toward the upstream side of the connecting pipe P in the inserting direction. A ball-shaped taper 15 is formed. On the upstream side of the packing fitting groove 14 in the insertion direction of the connecting pipe P, an annular protrusion fitting concave groove 14a deeper than the packing fitting groove 14 is provided, and the connecting pipe P is inserted in the inner diameter portion of the packing 4 On the upstream side, an annular projection 4d that fits into the projection fitting groove 14a is formed. An annular ridge 4e having an inner diameter smaller than the diameter of the packing fitting groove 14 is formed in the inner diameter portion corresponding to the radially inner side of the seal portion 4a of the packing 4.

  As shown in FIG. 1, the retaining ring 5 is a stainless steel product, and has an elastically expandable / reducible deformable biting tooth 5a on the inner diameter portion of the dish-shaped cross section. The outer diameter portion of the retaining ring 5 is interposed between the step portion 16 provided on the inner back side of the projection 12 on the inner periphery of the cap 6 and the opening end surface of the outer cylinder 3, and the biting teeth 5 a are connected. It protrudes into the tube insertion gap 8.

  Next, a usage mode of the plug-in type pipe joint having the above configuration will be described. In the on-site construction, the connecting pipe P is cut to a required length. The end of the cut connection pipe P is inserted into the connection pipe receiving port 13. At this time, when the end of the connection pipe P passes through the packing 4, first, as shown in FIG. 2, the dust removal cleaning portion 4b located upstream of the connection pipe P in the insertion direction of the packing 4 is first attached to the connection pipe P. The seal portion 4a is fitted in as shown in FIG. For this reason, when the end surface of the connecting pipe P hits the seal part 4a of the packing 4 as shown in FIG. 2, the dust removal cleaning part 4b of the packing 4 is already fitted in the connecting pipe P. The packing 4 in a state where the dust removal cleaning part 4b is fitted in the connecting pipe P is moved to some extent in the axial direction because the dust removal cleaning part 4b is pressed from the radially outer side and pressed against the packing fitting groove 14. It is in a regulated state. Therefore, even if the connecting pipe P is pushed deeper as shown in FIG. 3 from the state where the connecting pipe P hits the seal portion 4a of the packing 4 as shown in FIG. 2, the packing 4 is pushed out of the packing fitting groove 14 by the connecting pipe P. There is no.

  Moreover, when inserting the connecting pipe P, as described above, first, the dust removal cleaning portion 4b of the packing 4 is first fitted into the connecting pipe P and is in sliding contact with the inner face of the connecting pipe P. The dust and foreign matters adhering to the dust are surely removed by the dust removing cleaning part 4b, and the dust and foreign substances are not bitten between the inner peripheral surface of the connecting pipe P and the seal part 4a of the packing 4, It is possible to prevent the seal portion 4a from being damaged or the sealing performance from being deteriorated.

  In addition, the packing 4 is formed with an annular groove 4c that is recessed radially inward from the outer peripheral surface of the inner cylinder 2 between the seal portion 4a and the dust removal cleaning portion 4b. It effectively functions as a relief of the dust removal cleaning portion 4b that is pressed inward in the radial direction by the connecting pipe P and compressively deforms. Therefore, the dust removal cleaning part 4b can be easily compressed and deformed when pressed inward in the radial direction by the connecting pipe P, whereby dust and foreign substances can be more reliably removed by the dust removal cleaning part 4b. Further, since the concave groove 4c functions effectively as a relief of the seal portion 4a that is compressed and deformed by being pressed radially inward by the connecting pipe P, the seal portion 4a is pressed radially inward by the connecting pipe P. Sometimes it can be easily compressed and deformed, and the connecting pipe P can be easily inserted.

  Since the taper 15 which is gradually narrowed in the upstream direction in the insertion direction is formed on the upstream end surface side of the connecting pipe P in the dust removal cleaning portion 4b, when the connecting pipe P is inserted, the packing 4 is removed. It is easy to fit the cleaning part 4b into the connecting pipe P. Further, the packing 4 moves in the axial direction when the dust removal cleaning portion 4b and the seal portion 4a of the packing 4 are pressed by the connecting pipe P due to the fitting of the annular protrusion 4d and the protrusion fitting concave groove 14a. Can be reliably controlled, and the packing 4 can be more effectively prevented from being pushed out from the packing fitting groove 14.

  Since an annular ridge 4e having an inner diameter smaller than the diameter of the packing fitting groove 14 is formed on the inner diameter portion corresponding to the radially inner side of the seal portion 4a of the packing 4, the annular ridge 4e is connected As the seal portion 4 a is pressed radially inward by the pipe P, the pressure is locally pressed to the bottom of the packing fitting groove 14 to compress and deform to increase the contact pressure of the packing 4 against the bottom of the packing fitting groove 14. And the movement of the packing 4 in the axial direction can be effectively prevented.

  As shown in FIG. 3, when the end of the connection pipe P is completely inserted into the connection pipe insertion gap 8, the seal portion 4 a of the packing 4 comes into close contact with the inner peripheral surface of the connection pipe P in a compressed manner. Thus, a state is obtained in which the space between the inner peripheral surface of the connecting pipe P and the outer peripheral surface of the inner cylinder 2 is obtained, and the biting teeth 5a of the retaining ring 5 bite into and engage with the outer peripheral surface of the connecting pipe P. A P retaining state is obtained.

  The concave groove 4c of the packing 4 of the above embodiment is formed in a tapered surface so as to gradually become deeper toward the dust removal cleaning part 4b as shown in FIG. 5, but instead of this, as shown in FIG. The concave groove 4c can be formed in a stepped shape that is deeper on the dust removal cleaning part 4b side (4c1) and shallower than that on the seal part 4a side (4c2). Further, as shown in FIGS. 7 and 8, the annular protrusion 4 d can be formed on the inner diameter portion of the packing 4 so as to be omitted. In this case, the bottom of the packing fitting groove 14 is formed in a flat shape without the protrusion fitting groove 14a.

  In another reference example, as shown in FIG. 9, the groove side wall 14 b on the downstream side in the insertion direction of the connecting pipe P in the packing fitting groove 14 is formed in a taper that gradually expands toward the groove bottom of the packing fitting groove 14. can do. According to this, when the packing 4 is pushed in the inserting direction of the connecting pipe P due to the insertion of the connecting pipe P, the downstream end surface wall 4f of the connecting pipe P of the packing 4 contacts the taper of the groove side wall 14b. Since it receives the effect | action pushed toward the bottom of the fitting groove 14, it can prevent more effectively that the packing 4 is extruded from the packing fitting groove 14. FIG.

In the preferred embodiment of the present invention, as shown in FIGS. 10 and 11, the downstream end wall 4 f in the insertion direction of the connection pipe P in the packing 4 is gradually narrowed toward the downstream side of the connection pipe P in the insertion direction. It can be formed in a taper. According to this, when the packing 4 is pushed in the insertion direction of the connection pipe P by the insertion of the connection pipe P, the downstream end surface wall 4f of the connection pipe P of the packing 4 in the insertion direction downstream side of the packing fitting groove 14 is inserted. The groove 4 is abutted against the groove side wall 14b and pressed toward the bottom of the packing fitting groove 14, so that the packing 4 can be more effectively prevented from being pushed out of the packing fitting groove 14.
In the case of a preferred embodiment of the present invention, the groove side wall 14b on the downstream side in the insertion direction of the packing fitting groove 14 is formed on a vertical wall with respect to the bottom of the packing fitting groove 14 as shown in FIG. In the reference example, as shown in FIG. 12, it is arbitrary to form a taper that gradually widens toward the groove bottom of the packing fitting groove 14.

  The invention according to the reference example described above can be similarly applied to the joint body 1 having a cross-sectional shape as shown in FIG. In the reference example shown in FIG. 13, when the connecting pipe P is inserted, the insertion guide ring 20 to be inserted into the joint body 1 is incorporated prior to the connecting pipe P, the structure of the retaining ring 21 itself, and the retaining. The method of assembling the ring 21 to the joint body 1 is different from the retaining ring 5 of the above reference example, and other configurations and operations of the inner cylinder 2 and packing 4 are the same as those of the above embodiment and reference examples. The same members and the same elements are denoted by the same reference numerals, and detailed description thereof is omitted.

  The joint body 1 of this reference example is formed in a cylindrical shape, and the fluid passage 7 is formed in a penetrating shape in the axial direction. An opaque guide ring concealing cylinder 17 is axially formed from one axial end of the joint body 1 in the axial direction. The outer cylinder 2 protrudes integrally in parallel with the central axis O of the fluid passage 7 and guides the inner cylinder 2 longer than the guide ring concealment cylinder 17 from the inside of the guide ring concealment cylinder 17 at one end of the joint body 1. Concentrically with the concealing cylinder 17, it projects integrally outward in the axial direction, and a fluid passage 7 is formed in the inner cylinder 2 in communication. Between the outer periphery of the inner cylinder 2 and the inner periphery of the guide ring concealing cylinder 17, a guide ring entry space 18 into which the insertion guide ring 20 finally enters after the connection pipe P is inserted is formed. A male screw 19 is provided on the outer periphery of the guide ring concealing cylinder 17. The axial depth of the guide ring entry space 18 is formed to be equal to or deeper than the axial length of the insertion guide ring 20. The guide ring concealing cylinder 17 is formed separately from the joint body 1 and integrally joined to one end of the joint body 1 instead of being integrally formed at one end of the joint body 1. May be.

  The joint body 1 includes an outer cylinder 22 formed in a cylindrical shape with a resin that is transparent or translucent and can be seen through, and a female screw 23 is provided on the inner periphery of the rear end portion of the outer cylinder 22. The outer tube 22 is screwed and connected to the male screw 19 of the guide ring concealing tube 17, and the connecting tube for receiving the end of the connecting tube P between the inner periphery of the outer tube 22 and the outer periphery of the inner tube 2. The receiving port 24 is formed to communicate with the guide ring entry space 18.

  The retaining ring 21 is made of a wire material such as stainless steel, and a biting tooth 21a that bites into the outer peripheral surface of the connecting pipe P inserted into the connecting pipe receiving port 24 is provided on the inner diameter portion thereof. A part of the circumference of 21 is cut off, and the entire retaining ring 21 is formed so as to be capable of expanding and contracting its diameter.

The retaining ring 21 is housed in an annular retaining ring housing recess 25 provided on the inner periphery of the outer cylinder 22 on the front opening end side, and the inner circumferential surface on the axially outer side in the retaining ring housing recess 25. The taper surface 26 for applying a force in the diameter reducing direction to the retaining ring 21 is formed so as to be constricted toward the opening end of the outer cylinder 22.
As a means for providing the retaining ring housing recess 25 on the inner periphery of the outer cylinder 22, a cylindrical spacer 27 that is transparent or translucent and transparently visible inside the outer cylinder 22 is provided as a guide ring concealing cylinder. 17 is fitted on the extended line of the distal end portion via a backup rubber 28, and a retaining ring receiving recess 25 is provided between the opening end surface (axially outer end surface) of the spacer 27 and the tapered surface 26. Form. According to this, the outer cylinder 22 can be easily molded with a simple molding die structure, and the retaining ring 21 can be easily incorporated into the retaining ring housing recess 25. However, the present invention is not limited to this, and the retaining ring accommodating recess 25 can be formed by cutting the inner periphery of the outer cylinder 22 without using such a spacer 27.

  The insertion guide ring 20 is a resin molded product such as nylon, and is colored differently from the color of the outer surface of the connection pipe P so that it can be clearly distinguished from the connection pipe P. For example, when the color of the connection pipe P is white, the insertion guide ring 20 is blue, red, or green. The inner diameter portion of the insertion guide ring 20 has a taper 20a that expands rearward gradually from the front end portion toward the rear, and the outer diameter portion moves from the rear end portion toward the front, contrary to the inner diameter portion. A taper 20b having a front expanding shape that gradually expands is provided to form a V-shaped cross section. The insertion guide ring 20 is also fluorescent / phosphorescent so that it can be easily confirmed even in a dark place by applying a luminescent paint using a phosphor / phosphor or molding with a synthetic resin containing a luminescent pigment. Can be formed. The insertion guide ring 20 is assembled between the inner periphery of the retaining ring 21 and the outer periphery of the front opening end of the inner cylinder 2 with the front end directed toward the inlet side of the connection tube receiving port 24.

  Since the packing fitting groove 14 is provided in the outer peripheral surface of the inner cylinder 2 of the joint body 1 and the packing 4 is fitted in the packing fitting groove 14, it is the same as in the case of the above embodiment and the reference example. The repeated explanation is omitted.

  Next, a usage mode of the plug-in type pipe joint having the above configuration will be described. In on-site construction, first, the connecting pipe P is cut to a required length. As shown in FIG. 14, the cut end of the connection pipe P is inserted into the connection pipe receiving port 24, and the insertion guide ring 20 is pushed from the front of the connection pipe P at the end thereof to be connected. It is pushed inwardly of the tube receiving port 24. The insertion guide ring 20 to be pushed is pushed out by the taper 20b of the outer diameter portion to widen the retaining ring 21 and expanded, and the dust removal cleaning portion 4b protruding from the outer peripheral surface of the inner cylinder 2 by the taper 20a of the inner diameter portion. The seal portion 4a passes while being compressed inward in the radial direction. In this way, the taper 20a of the insertion guide ring 20 passes through the dust removal cleaning portion 4b and the seal portion 4a protruding from the outer peripheral surface of the inner cylinder 2 while being compressed, so that the inner periphery of the end portion of the connecting pipe P is chamfered in advance. Even if it is not processed, the connecting pipe P can be smoothly inserted without sticking to the packing 4.

  As described above, whether or not the connection pipe P normally pushes the insertion guide ring 20 and whether or not the insertion guide ring 20 and the connection pipe P normally pass through the retaining ring 21 are determined by the outer cylinder. Since 22 is transparent or translucent, and the insertion guide ring 20 is given a color different from that of the connecting pipe P and can be easily distinguished from the connecting pipe P, it can be easily visually confirmed from the outside. Therefore, for example, there is a problem that the connecting pipe P is inserted obliquely and the insertion guide ring 20 is not pushed normally, or the insertion guide ring 20 does not normally pass through the retaining ring 21. If it occurs, this can be discovered very quickly, so that the insertion of the connecting pipe P can be immediately stopped and reinserted.

  When the end of the connecting pipe P passes through the packing 4 following the insertion guide ring 20, the dust removal cleaning part 4b of the packing 4 is first fitted into the connecting pipe P first, and then the seal part 4a is fitted. Therefore, when the end surface of the connecting pipe P abuts against the seal portion 4a of the packing 4, the dust removal cleaning portion 4b of the packing 4 is already fitted in the connecting pipe P. Therefore, the connecting pipe P is sealed with the packing 4. Even if it is pushed deeper from the state where it hits the portion 4a, it is possible to prevent the packing 4 from being pushed out of the packing fitting groove 14 by the connecting pipe P, and when the connecting pipe P is inserted, it adheres to the inner surface of the connecting pipe P. The dust and foreign matters that are being removed are surely removed by the dust removal cleaning section 4b, and the dust and foreign substances are not caught between the inner peripheral surface of the connecting pipe P and the seal portion 4a of the packing 4. Scratching the seal portion 4a, for it, etc. can be prevented from being lowered sealing performance is the same as in the above Examples and Reference Examples.

As shown in FIG. 14, when the end of the connection pipe P is completely inserted to the back of the connection pipe receiving port 24, the seal portion 4 a of the packing 4 is in close contact with the inner peripheral surface of the connection pipe P in a compressed manner. A state of sealing between the inner peripheral surface of the connecting pipe P and the outer peripheral surface of the inner cylinder 2 is obtained, and the biting teeth 21a of the retaining ring 21 bite into and engage with the outer peripheral surface of the connecting pipe P. Can be obtained.
When the end of the connection pipe P is completely inserted to the back of the connection pipe receiving port 24 as shown in FIG. 13, the insertion guide ring 20 reaches the guide ring entry space 18 in the opaque guide ring concealing cylinder 17. In the case of insufficient insertion, the insertion guide ring 20 may go out of the guide ring concealment cylinder 17 without entering the guide ring entry space 18. Since it will be visible, it can be easily confirmed whether or not the end of the connecting pipe P has been completely inserted to the back of the connecting pipe receiving port 24. Accordingly, it is possible to prevent poor insertion or insufficient insertion of the connecting pipe P that causes water leakage.

  After the connection pipe P is inserted, when the connection pipe P is pulled in the extraction direction, the outer peripheral surface of the retaining ring 21 that accompanies the connecting pipe P abuts against the tapered surface 26 of the outer cylinder 22, so that the retaining ring 21 is By reducing the diameter, the biting of the biting teeth 21a on the outer peripheral surface of the connecting pipe P increases. Thus, by increasing the biting of the retaining ring 21 into the outer peripheral surface of the connecting pipe P, the connecting pipe P is reliably prevented from coming out from the connecting pipe receiving port 24.

  The present invention can be similarly applied when the joint body 1 is any of a socket type, an elbow, a T type, and the like.

P Connection pipe 1 Joint body 2 Inner cylinder 4 Packing 4a Sealing part 4b Debris cleaning part 4c Groove 4d Annular projection 4e Annular protrusion 4f Downstream end wall of the gasket connection pipe insertion direction 14 Packing fitting groove 14a Protrusion fitting depression Groove 14b Groove side wall

Claims (3)

An inner cylinder into which the end of the connection pipe is inserted into an outer fitting shape is provided inside the joint body, an annular packing fitting groove is provided on the outer peripheral surface of the inner cylinder, and the connection pipe is provided in the packing fitting groove. In the plug-in type pipe joint that is fitted with a packing for sealing between the inner periphery of the end and the outer periphery of the inner cylinder,
The packing forms a seal portion that protrudes radially outward from the outer peripheral surface of the inner cylinder in a state of being fitted in the packing fitting groove, and the connecting pipe is inserted more than the seal portion in the packing. A dust removal cleaning portion is formed at a position corresponding to the upstream side in the direction and protrudes radially outward from the outer peripheral surface of the inner cylinder,
The groove side wall of the packing fitting groove on the downstream side in the insertion direction of the connecting pipe is formed in a vertical wall with respect to the bottom of the packing fitting groove, and the groove opening side end of the groove side wall is the connection in the packing. It is formed so as to be located on the radially outer side of the inner cylinder from the outer peripheral side end of the end wall on the downstream side in the tube insertion direction,
The plug-type pipe joint according to claim 1, wherein an end face of the packing on the downstream side in the connecting pipe insertion direction is formed in a tapered shape gradually toward the downstream side in the connecting pipe insertion direction.   2. The insertion according to claim 1, wherein an annular groove is formed in a circumferential direction between the seal portion and the dust removal cleaning portion of the packing and is recessed radially inward from the outer peripheral surface of the inner cylinder. Type pipe fittings.   The plug-in type pipe according to claim 1 or 2, wherein a tapered taper is formed gradually toward the upstream side in the insertion direction of the connection pipe on the upstream end face side of the connection pipe in the dust removal cleaning section. Fittings.

Images