HK1176984A1

HK1176984A1 - Pipe joint

Info

Publication number: HK1176984A1
Application number: HK13103745.7A
Authority: HK
Inventors: 太田浩司; 水野宏俊; 北島典和; 北岛典和; 中居義貴; 中居义贵; 長谷川博; 长谷川博一
Original assignee: 安隆化成株式會社; 安隆化成株式会社
Priority date: 2011-03-22
Filing date: 2013-03-25
Publication date: 2013-08-09
Also published as: CN102691840B; CN102691840A

Abstract

The invention provides a bulk type pipe joint provided with a special connecting pipe into which a confirming mechanism can be inserted, wherein the insertion of the connecting pipe and the connecting operation are simple, and the pipe joint can be used for easily and accurately grasping whether the inserted connecting pipe reaches any determined position in the pipe joint during connection. The pipe joint is characterized by being provided with a C-type annular or O-type annular part which is of a radiate extensional flexible rod-shaped part and is arranged in the accommodating part of the pipe joint. By virtue of adjusting the length of the rod-shaped part, when the connecting pipe is inserted, the annular part is pressed in an inner direction by the connecting pipe, the rod-shaped part which is previously arranged in a through hole can be pulled into an outer barrel body from the exterior of the outer barrel body, and the inserting confirming position of the length of the connecting pipe relative to the accommodating part of the pipe joint is freely changed.

Description

Pipe joint

Technical Field

The present invention relates to a pipe joint for connecting pipes in a straight-insertion type (onetouch) including a connecting pipe insertion confirmation mechanism, and more particularly, to a straight-insertion type pipe joint including an outer cylinder and an inner cylinder forming a receiving portion for receiving a connecting pipe, having a connection pipe insertion and connection operation unit, and having a dedicated connecting pipe insertion confirmation mechanism, and capable of accurately and easily grasping whether or not an inserted connecting pipe reaches an arbitrarily determined position in the pipe joint and performing connection.

Background

A pipe joint for connecting pipes in a straight-line manner is known. For example, JP 4-18793 a (patent document 1), JP 2001-193883 a (patent document 2), and JP 2003-227592 a (patent document 3) disclose a one-piece pipe joint in which a cylindrical lock ring having a protrusion such as a tooth or claw for locking a connection pipe is provided between an inner cylindrical body concentrically arranged and an outer cylindrical body having a tapered surface reducing the diameter toward an insertion port and is movable in an axial direction. In the pipe joint, after the connection pipe is inserted into the deepest portion, the lock ring is moved to the vicinity of the insertion port by pulling back. Then, the projection of the lock ring is reduced in diameter so as to bite into the outer peripheral surface of the connection pipe by the interaction with the tapered surface formed near the insertion port of the outer cylinder, thereby preventing the connection pipe from dropping.

JP 2005-172218 a (patent document 4) discloses a one-way pipe joint of a type not including an inner cylinder for receiving a connection pipe inserted into the inside of the pipe joint from the inside, which has substantially the same structure as the pipe joint described in the above-mentioned patent documents 1 to 3.

Further, WO2006/135227 (patent document 5) describes another modification of the pipe joint described in the above patent documents 1 to 3. In the direct-insertion type pipe joint described in patent document 5, both the outer sleeve and the inner sleeve have tapered surfaces facing each other to narrow the gap of the insertion port, and a cylindrical lock ring (1ock ring) composed of an outer clip ring (grip ring) and an inner clip ring (grip ring) having teeth and concentrically arranged and a bottom portion connecting both clip rings at the deepest portion is arranged to be movable in the axial direction so that the connection pipe can be inserted therebetween.

Further, as a straight-insertion type pipe joint other than the type having a lock ring movable in an axial direction inside the pipe joint, straight-insertion type pipe joints described in JP 9-236190 a (patent document 6), JP 2006-118704 a (patent document 7), and JP 2008-164074 a (patent document 8) are known. The direct insertion type pipe joint described in patent documents 6 to 8 is configured by an outer cylinder concentrically arranged and an inner cylinder extending from a joint body in order to form a housing portion for housing a connection pipe, and an annular lock ring having a plurality of radially extending teeth or claws which bite into an inner circumferential surface of the connection pipe to prevent the connection pipe from coming off is fixed to an outer circumferential surface of the inner cylinder.

Further, although basically the same structure as the pipe joint described in the above patent documents 6 to 7 is provided, as described in JP 2002-.

Further, as described in JP 2010-230094 (patent document 11), the present inventors have proposed a direct-insert type pipe joint in which a bent lock ring is provided in a coupling pipe housing portion of the pipe joint, the lock ring is deformed to expand in an axial direction when pressed in a radial direction, and a free end of the lock ring having a claw portion is displaced so as to press against an inner circumferential surface and/or an outer circumferential surface of the coupling pipe by interaction with a surrounding tapered wall when the coupling pipe is inserted.

In these pipe joints, in order to connect a connection pipe such as a circular pipe made of a plastic material or an aluminum triple-layer pipe having a structure in which aluminum is sandwiched between front and rear surfaces of the pipe joint in a straight line, the connection pipe needs to be inserted into a predetermined position in the pipe joint or the pipe joint inserted into the predetermined position needs to be pulled back to a position where the claw of the lock ring bites into the pipe joint. If the inserted connection pipe does not reach a predetermined position in the pipe joint, the connection pipe may be easily detached from the pipe joint or a poor seal may be caused between the connection pipe and the pipe joint.

However, it is generally relatively easy to confirm whether or not the connection pipe is inserted into the pipe joint, but it is not easy to confirm whether or not the inserted connection pipe reaches a predetermined position. Therefore, there is a problem that the connection operation is terminated before the inserted connection pipe reaches a predetermined position in the pipe joint, or conversely, the insertion operation is continued even though the connection pipe reaches the deepest portion in the pipe joint, and as a result, an excessive load is applied to the pipe joint or the connection pipe, and they are broken.

In order to solve the above-described problem, as a means for facilitating confirmation of whether or not the inserted connection pipe reaches a predetermined position in the pipe joint, as described in JP 11-132374 a (patent document 12), there is known a pipe joint in which a confirmation hole or a transparent portion for visually confirming the tip position of the connection pipe in a connection completed state is provided in an outer cylinder of the pipe joint.

Further, as examples of the joint pipe insertion confirmation mechanism which requires exclusive use, there are known a type of joint pipe in which a rod-like insertion confirmation member which is movably fitted (loosely fitted) in a through hole of an outer cylinder of the joint pipe is pushed up by an end portion of the joint pipe to be inserted and protrudes to the outside of the outer cylinder, as described in JP hei 6-62292 a (patent document 13), JP 2001 + 324071 a (patent document 14), and JP 2002 + 89759 a (patent document 15). Further, a pipe joint is known in which a seal ring supporting a rod-like insertion confirmation member protruding outward from the inside of the pipe joint is removed by a connection pipe inserted, and as a result, the insertion confirmation member having lost the support ring is inserted into a through hole from the outer peripheral surface of the outer cylinder, as described in JP 2009-19645 a (patent document 16).

However, these types of pipe joints and connection pipe insertion confirmation mechanisms are only able to confirm whether or not an inserted connection pipe has arrived at a position where a confirmation hole or connection pipe insertion confirmation mechanism is disposed, and cannot confirm whether or not a connection pipe has arrived at an arbitrarily determined position in a pipe joint, for example, at an intermediate portion or the deepest portion of a housing portion.

In addition, in the case of a pipe joint of the type in which the insertion state of the connection pipe is visually confirmed, there is a problem that the pipe joint does not function effectively in a dark place, a claustrophobic place, or the like. Further, in the case of a pipe joint of the type requiring a dedicated connection pipe insertion confirmation mechanism, due to structural constraints, it is not possible to obtain a large amount of protrusion (protrusion height) of the insertion confirmation member to the outside or a large amount of penetration (penetration depth) into the through hole, and therefore there is a problem that the operator cannot correctly confirm the state of the unevenness of the insertion confirmation member.

Documents of the prior art

Patent document

Patent document 1: JP Kokai No. 4-18793A

Patent document 2: JP 2001-193883A

Patent document 3: JP 2003-A227592

Patent document 4: JP 2005-172218 publication

Patent document 5: WO2006/135227 publication

Patent document 6: JP-A9-236190

Patent document 7: JP 2006-118704 publication

Patent document 8: JP 2008-164074 publication

Patent document 9: JP 2002-106772 publication

Patent document 10: JP patent application publication No. 2003-307290

Patent document 11: JP 2010-230094A

Patent document 12: JP-A11-132374

Patent document 13: JP Kokai No. 6-62292

Patent document 14: JP 2001-324071 publication

Patent document 15: JP 2002-89759A

Patent document 16: JP 2009-19645 publication

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a straight-insertion type pipe joint including a dedicated connection pipe insertion confirmation mechanism that is easy to insert and connect a connection pipe and that is capable of accurately and easily grasping whether or not the inserted connection pipe has reached an arbitrarily determined position in the pipe joint at the time of connection.

Accordingly, the present inventors have made active studies on a direct insertion type pipe joint having a dedicated connection pipe insertion confirmation mechanism. As a result, the present inventors have found that when a C-ring-shaped or O-ring-shaped member having a flexible rod-shaped member extending radially is disposed in a receiving portion of a pipe joint and the length of the rod-shaped member is adjusted, the ring-shaped member is pushed into the inside by a coupling pipe when the coupling pipe is inserted, and when the rod-shaped member provided in advance in a through hole is pulled into the inside from the outside of an outer cylinder, the insertion confirmation position of the coupling pipe with respect to the length of the receiving portion of the pipe joint can be freely changed, thereby completing the pipe joint of the present invention.

That is, according to the present invention, there is provided a direct insertion type pipe joint including a joint body, an outer cylinder and an inner cylinder forming a housing portion for housing a connection pipe, and a connection pipe insertion confirmation mechanism for confirming an insertion state of the connection pipe, wherein the insertion confirmation mechanism includes: a through hole penetrating the inner circumferential surface and the outer circumferential surface of the outer cylinder; a groove portion formed on an inner peripheral surface of the outer cylinder and extending from the through hole to an inside in an axial direction; and a C-ring-shaped or O-ring-shaped insertion confirmation member that has a flexible rod-shaped member extending radially and is disposed movably in the housing portion in the axial direction, wherein the rod-shaped member is disposed so as to protrude from the through hole toward the outside of the outer cylinder before the connection pipe is inserted, and wherein the rod-shaped member is drawn in from the outside of the outer cylinder to be housed in the groove formed in the inner circumferential surface of the outer cylinder by pressing the insertion confirmation member toward the inside in the axial direction from the distal end portion of the connection pipe when the connection pipe is inserted.

In the one-touch type pipe joint provided with the dedicated joint pipe insertion confirmation mechanism of the present invention, the flexible rod-like members radially extending from the C-ring-shaped or O-ring-shaped insertion confirmation member are arranged in the housing portion of the pipe joint so as to protrude outward from the through hole of the outer cylinder in an initial state before the joint pipe is inserted. Therefore, normally, the insertion confirmation member connected to the rod-like member is disposed substantially directly below the through hole of the outer cylinder, and the length of the rod-like member can be adjusted to freely change the protruding length from the outer circumferential surface of the outer cylinder, so that the operator can easily confirm the initial state of the connection pipe before insertion.

On the other hand, when the connection pipe is inserted into the housing portion of the pipe joint, the insertion confirmation member occupies the entire or a part of the cross section of the housing portion, abuts against the tip end portion of the connection pipe, and is then pressed into the deepest portion of the pipe joint housing portion. At this time, since the rod-like member is connected to the insertion confirmation member body, the rod-like member is press-fitted into the groove formed in the inner peripheral surface of the outer cylindrical body from the outside of the outer cylindrical body through the through hole and is accommodated in the groove along with the movement of the insertion confirmation member.

Therefore, the operator can visually and with fingers, etc., check the through hole of the outer cylinder that has become empty, and can easily and accurately grasp whether or not the inserted connection pipe has reached a predetermined position with respect to the pipe joint, and whether or not the connection has been completed.

As described above, the connection tube insertion confirmation mechanism used in the present invention may be configured such that the length of the rod-like member is adjusted to be substantially equal to the distance between the distal end position of the connection tube and the through hole of the outer cylinder when the connection of the connection tube is completed. Thus, when the inserted connection pipe reaches the position where the connection is completely completed, the rod-shaped members are all pulled into the through-holes from the outside of the outer cylindrical body or pulled into the groove formed in the inner circumferential surface of the outer cylindrical body through the through-holes, and are stored. In this way, the pipe joint of the present invention can freely change the insertion depth of the connection pipe with respect to the length of the housing portion of the pipe joint, that is, the insertion confirmation position of the connection pipe, by adjusting the length of the rod-shaped member of the connection pipe insertion confirmation mechanism.

In addition, a plurality of rod-shaped members may be arranged on the insertion confirmation member body, and in this case, through holes corresponding to the number and positions of the rod-shaped members need to be provided in the outer cylinder.

Further, the reason why it is sufficient that the length of the rod-like member is not strictly equal to the distance from the through hole to the tip end position of the connection pipe, and is "substantially" equal to each other is that: in practice, there are factors that cause errors in the depth of the through-hole (thickness of the outer cylindrical body), the extension of the rod-like member when it is bent and pulled in, the curvature of the bent portion, and the like.

In the present invention, the inner peripheral surface of the outer cylinder is formed with a groove portion at least from the through hole toward the inside in the axial direction. If the groove is not formed on the inner peripheral surface of the outer cylinder, the following disadvantages are caused: the rod-like member drawn into the housing portion with the insertion of the connection pipe is sandwiched between the inner peripheral surface of the outer cylinder and the outer peripheral surface of the connection pipe, and hinders the further insertion of the connection pipe or is crushed (see きちぎゐ).

In the present invention, the space provided between the inner peripheral surface of the outer cylinder and the outer peripheral surface of the connection pipe for drawing in the rod-like member is formed with a separate groove portion instead of a gap portion due to a difference in diameter between the inner diameter of the outer cylinder and the outer diameter of the connection pipe. The reason is that: if the gap portion is used, the connection pipe cannot be firmly fixed due to rattling (rickety) of the gap portion between the inserted connection pipe and the outer cylinder. On the other hand, in the case where the groove portion is formed in a part of the inner peripheral surface of the outer cylinder, the inner diameter of the outer cylinder can be designed to be substantially the same as the outer diameter of the connection pipe, and therefore, the connection pipe can be inserted and fixed without rattling. Further, the inner diameter of the outer cylinder is set larger than the outer diameter of the connection pipe, and the inner circumferential surface of the outer cylinder is provided with a plurality of ribs extending radially from the inner circumferential surface of the outer cylinder, the ribs having end portions terminating substantially on the outer circumferential surface of the connection pipe.

Further, the groove portion of the outer cylinder may be formed by setting the inner diameter of the outer cylinder to be larger than the outer diameter of the connection pipe, and fitting a sleeve having a slit extending in the axial direction and having an inner diameter substantially equal to the outer diameter of the connection pipe. That is, the slit portion after the sleeve is attached forms a groove portion on the inner peripheral surface of the outer cylinder.

The sleeve has an O-shape in cross section that is generally in close contact with the inner circumferential surface of the outer cylinder. However, in the case of the present invention, in view of ease of mounting, the sleeve may be formed in a C-shape with a part of the cross section cut away, so that the outer diameter thereof may be deformed to be small when the sleeve is mounted on the inner circumferential surface of the outer cylindrical body.

The use of such a sleeve can improve the formability of the outer cylinder and the mountability of internal parts such as an insertion confirmation member, a lock ring, and a seal ring. In particular, in the case of a pipe joint of the type using a lock ring described later, a fixing wall parallel to the radial direction for restricting the axial movement of the lock ring can be easily formed on the inner peripheral surface of the outer cylinder, which is convenient.

In the present invention, the rod-like member is accommodated in the groove portion on the inner peripheral surface of the outer cylindrical body while being deformed in a bending manner in accordance with the movement of the insertion confirmation member toward the inside in the axial direction. Therefore, the rod-like member and the insertion confirmation member including the same are preferably made of a material having flexibility and high tensile stress resistance, and examples of such a material include thermoplastic elastomers, synthetic rubbers, natural rubbers, and the like. In particular, in the case of a thermoplastic elastomer, the elongation under a constant load is generally smaller than that of synthetic rubber or natural rubber, and therefore, the thermoplastic elastomer is suitable as a material for a rod-like member that is required to be deformed in a bending manner while maintaining a length corresponding to the insertion confirmation position of the connection pipe.

In addition, in order to obtain high deformation characteristics of the rod-like member, the shape of the rod-like member may be improved so as to be easily bent, such as by forming the cross section of the rod-like member into a flat shape. In particular, the rod-like member has a nearly hinge structure having a smaller cross-sectional area than the other portions by narrowing the cross-sectional area of the rod-like member near the root of the annular insertion confirmation member body, thinning the rod-like member, or the like, and thus can obtain high bending characteristics at the initial stage of drawing.

Further, the shape of the tip portion of the rod-like member is not particularly limited, and the shape can be easily confirmed by an operator with a finger or the like, and therefore the shape can be formed into a shape that can stimulate the finger, such as a shape in which the tip portion is tapered or a surface having irregularities. In addition, the rod-like member or the tip portion of the rod-like member may be colored in a conspicuous color such as a fluorescent color in order to improve visibility for visual observation.

The direct insertion type pipe joint having the dedicated connection pipe insertion confirmation mechanism of the present invention may be constituted by: the pipe joint is characterized in that the pipe joint further comprises the inner cylinder and an inner lock ring, the inner cylinder further comprises a fixed wall parallel to the radial direction and a tapered wall continuously expanding in diameter towards the outside in the axial direction on the outer circumferential surface, the inner lock ring is a cylindrical body having a plurality of slits for forming a free end of a cantilever beam (cantilever), and has a first outward claw portion which presses the inner circumferential surface of the connecting pipe by elastic deformation of the cylindrical body when the connecting pipe is inserted and a second outward claw portion which is arranged on the free end and locks the connecting pipe when the connecting pipe is pulled out, the inner lock ring is arranged to be movable in the axial direction between the fixed wall and the tapered wall of the inner cylinder, and after the connecting pipe is inserted to a predetermined position of the connecting pipe, when the inner lock ring is moved in the pulling direction, the inner lock ring is locked on the inner circumferential surface by the first outward claw portion and moves in the pulling direction together with the connecting pipe, the free end of the inner locking ring enters the tapered wall region of the inner cylinder, and then the inner locking ring expands in diameter by the interaction with the tapered wall in such a manner that the second outward claw is pressed against the inner peripheral surface of the connection pipe.

As another aspect, the one-touch type pipe joint having the dedicated connection pipe insertion confirmation mechanism of the present invention may be configured by: the pipe joint further includes the outer cylinder having a fixing wall parallel to a radial direction on an inner circumferential surface and a tapered wall continuously reducing a diameter toward an outer side in an axial direction, and an outer lock ring which is a cylindrical body having a plurality of slits for forming a free end of a cantilever beam (cantilever) and has a first inward claw portion which presses an outer circumferential surface of the connection pipe by elastic deformation of the cylindrical body when the connection pipe is inserted and a second inward claw portion which is disposed at the free end and which engages with the connection pipe when the connection pipe is pulled out, and which is disposed so as to be movable in the axial direction between the fixing wall and the tapered wall of the outer cylinder, and which is engaged with an outer circumferential surface of the connection pipe by the first inward claw portion when the connection pipe is moved in a pulling direction after the connection pipe is inserted to a predetermined position of the connection pipe, and moves in the pulling direction together with the connection pipe, the free end of the outer lock ring enters the tapered wall region of the outer cylinder, and then, by interaction with the tapered wall, the outer lock ring is reduced in diameter so as to press the second inward claw portion against the outer peripheral surface of the connection pipe.

Further, as another aspect, the one-touch type pipe joint having the dedicated connection pipe insertion confirmation mechanism of the present invention may be configured by: the pipe joint further includes the inner cylinder, the outer cylinder, an inner lock ring and an outer lock ring, the inner cylinder further includes a fixing wall parallel to a radial direction and a tapered wall continuously expanding in diameter toward an axially outer side on an outer circumferential surface, the outer cylinder further includes a fixing wall parallel to a radial direction and a tapered wall continuously reducing in diameter toward an axially outer side on an inner circumferential surface, the inner lock ring is a cylindrical body having a plurality of slits for forming free ends of the cantilever beams, and has a first outward pawl portion which presses an inner circumferential surface of the connection pipe by elastic deformation of the cylindrical body when the connection pipe is inserted and a second outward pawl portion which is disposed at the free end and which engages with the connection pipe when the connection pipe is pulled out, and the inner lock ring is disposed so as to be movable in an axial direction between the fixing wall and the tapered wall of the inner cylinder, and the outer lock ring is a cylindrical body having a plurality of slits for forming free ends of the cantilever beams, and has a first inward claw portion which presses an outer peripheral surface of the connection pipe by elastic deformation of the cylindrical body when the connection pipe is inserted, and a second inward claw portion which is disposed at the free end and engages with the connection pipe when the connection pipe is pulled out, and the outer lock ring is disposed so as to be movable in an axial direction between a fixed wall and a tapered wall of the outer cylindrical body, and when the connection pipe is moved in a pulling direction after the connection pipe is inserted to a predetermined position of the receiving portion, the inner lock ring is engaged with an inner peripheral surface of the connection pipe by the first outward claw portion and moves in the pulling direction together with the connection pipe, and a free end of the inner lock ring enters a tapered wall region of the inner cylindrical body, and then the inner lock ring expands in diameter by pressing the second outward claw portion against the inner peripheral surface of the connection pipe by interaction with the tapered wall, and the outer lock ring is engaged with the outer circumferential surface of the connection pipe by the first inward claw portion to move in the drawing direction together with the connection pipe, and a free end of the outer lock ring enters a tapered wall region of the outer cylinder and then is reduced in diameter by an interaction with the tapered wall so as to press the second inward claw portion against the outer circumferential surface of the connection pipe.

In the present invention, when a pipe joint having a structure further including an inner lock ring and/or an outer lock ring inside as described above is used, the joint body, the inner cylinder, and the outer cylinder each have a cylindrical shape, and the joint body may include the inner cylinder and be integrally formed with the inner cylinder. Preferably, the joint body and the inner cylinder have passage openings for fluid flow therein, and the tip end portions thereof have funnel shapes for reducing resistance to fluid flow. Further, when importance is attached to productivity, cost, and the like of the pipe joint, all the components of the joint main body, the inner cylinder, and the outer cylinder may be integrally formed.

In the case of a type in which the outer cylinder of the pipe joint is separated from the joint main body, the outer cylinder can be reliably fitted (firmly fitted) to the joint main body without rotating, or can be movably fitted (loosely fitted) to rotate freely in the circumferential direction. In the case where the outer cylinder is rotatably attached to the joint main body, this type of pipe joint can easily eliminate bending stress or rotational moment applied to the connection pipe at the time of connection or after connection, and therefore can relatively flexibly cope with breaking stress.

The material of the joint main body, the inner cylinder and/or the outer cylinder is not particularly limited as long as it is relatively hard, but it is preferably molded from a plastic material or a metal material. In particular, when the resin is molded from a plastic material, polyphenylene sulfone (PPSU) resin or polyphenylene sulfide (PPS) resin is more preferably used as the material.

A joint body including an inner cylinder and an outer cylinder are concentrically arranged, and a receiving portion for receiving a connection pipe is formed between the inner cylinder and the outer cylinder. A lock ring is disposed in the receiving portion of the pipe joint so as to be movable in the axial direction, and has a first claw portion that functions to press the circumferential surface of the coupling pipe when the coupling pipe is inserted and a second claw portion that functions to lock the coupling pipe when the coupling pipe is pulled out. The locking ring may be attached to either the outer peripheral surface of the inner cylinder or the inner peripheral surface of the outer cylinder, but it is preferable to dispose the locking rings on both the locking rings in order to reliably hold the connection pipe when one of the locking rings is damaged due to dropping of the pipe joint, adhesion of a solvent, stepping, or the like.

Therefore, in order to dispose the inner lock ring on the outer peripheral surface of the inner cylinder so as to be movable in the axial direction, a fixed wall parallel to the radial direction and a tapered wall continuously expanding in diameter toward the outside in the axial direction are formed. Further, in order to dispose the outer lock ring on the inner peripheral surface of the outer cylinder so as to be movable in the axial direction, a fixed wall parallel to the radial direction and a tapered wall continuously reducing the diameter toward the outside in the axial direction are formed. Further, by disposing the inner lock ring and/or the outer lock ring between the fixed wall and the tapered wall, the movement in the axial direction is substantially restricted by the relationship between one end (fixed end) of the inner lock ring and the fixed wall on the outer circumferential surface of the inner cylinder and/or the inner circumferential surface of the outer cylinder, and the movement in the axial direction is allowed by the relationship between the other end (free end) of the inner lock ring and the tapered wall. Therefore, the fixed end of the inner lock ring and/or the outer lock ring is disposed more inward in the axial direction than the free end, and the free end is disposed with a second claw portion for locking the connection pipe when pulled.

The inner lock ring disposed on the outer peripheral surface of the inner cylinder is formed of a cylindrical body, and a plurality of slits are cut in the body from the end of the cylindrical body to form the free end of the cantilever (cantilever). The inner lock ring has a first outward claw portion that acts to press the inner peripheral surface of the connection pipe by elastic deformation when the connection pipe is inserted, and a second outward claw portion that is disposed at the free end and acts to lock the connection pipe when the connection pipe is pulled out.

With regard to the function of pressing the first outward claw portion, the bulging portion of the inner lock ring has a cross-sectional shape in the axial direction like an inchworm (looper), and therefore bends when pressed radially inward, and presses the inner peripheral surface of the inserted connection pipe appropriately by the reaction force thereof. Further, since the slit extends in the axial direction so as to penetrate the body portion of the inner lock ring, the respective bulging portions divided by the slit do not interfere with each other, and elastic deformation is easy.

As a result, when the connection pipe is inserted into the receiving portion of the pipe joint and then moved in the pull-out direction, the first outward claw portion is engaged with the inner peripheral surface of the connection pipe, and therefore the inner lock ring is also moved in the pull-out direction together with the connection pipe. The free end of the inner locking ring enters the tapered wall region of the inner cylinder, and the inner locking ring expands in diameter by the interaction with the tapered wall so as to press the second outward claw portion against the inner peripheral surface of the connection pipe.

In this type of pipe joint, the first outward claw portion is supported by the body of the inner lock ring so as to press the inner peripheral surface of the inserted connection pipe appropriately, and the second outward claw portion is retracted so as to be hardly in contact with the inner peripheral surface of the connection pipe when not moving in the drawing direction after the connection pipe is inserted, and is supported by the free end of the inner lock ring. When the connection pipe is inserted, the connection pipe receives a small insertion resistance from the first outward claw portion, and when the connection pipe is moved in the drawing direction, the connection pipe is reliably and firmly locked by the interaction between the second outward claw portion and the tapered wall.

On the other hand, the outer lock ring disposed on the inner peripheral surface of the outer cylinder is formed of a cylindrical body, and a plurality of slits are cut from the end of the cylindrical body in the body portion thereof to form the free end of the cantilever (cantilever). The outer lock ring has a first inward claw portion that acts to press the outer peripheral surface of the connection pipe by elastic deformation when the connection pipe is inserted, and a second inward claw portion that is disposed at the free end and acts to lock the connection pipe when the connection pipe is pulled out.

With regard to the function of pressing the first inward claw portion, the narrowed portion (recessed portion) of the outer lock ring has an inchworm-like shape in its axial cross-sectional shape, and therefore bends when pressed radially outward, and presses the outer peripheral surface of the inserted connection pipe appropriately by its reaction force. Further, since the slit extends in the axial direction so as to penetrate the body portion of the outer lock ring, the respective narrowed portions divided by the slit do not interfere with each other, and elastic deformation is easy.

As a result, when the connection pipe is inserted into the receiving portion of the pipe joint and then moved in the pull-out direction, the first inward claw portion is engaged with the outer peripheral surface of the connection pipe, and therefore the outer lock ring is also moved in the pull-out direction together with the connection pipe. The free end of the outer lock ring enters the tapered wall region of the outer cylinder, and the outer lock ring is reduced in diameter by the interaction with the tapered wall so as to press the second inward claw portion against the outer peripheral surface of the connection pipe.

In this type of pipe joint, the first inward claw portion is supported by the main body of the outer lock ring so as to press the outer peripheral surface of the inserted connection pipe appropriately, and the second inward claw portion is retracted so as to be hardly in contact with the outer peripheral surface of the connection pipe when not moving in the drawing direction after the connection pipe is inserted, and is supported by the free end of the outer lock ring. When the connection pipe is inserted, the connection pipe receives a small insertion resistance from the first inward claw portion, and when the connection pipe is moved in the drawing direction, the connection pipe is reliably and firmly locked by the interaction between the second inward claw portion and the tapered wall.

In the case where both the inner lock ring and the outer lock ring are used in combination, the first outward claw portion of the inner lock ring and the first inward claw portion of the outer lock ring may be arranged to press the connection pipe at positions different from each other in the axial direction, or may be arranged to press the connection pipe at positions opposite to each other. Further, similarly to the first outward claw portion and the first inward claw portion, the second outward claw portion of the inner lock ring and the second inward claw portion of the outer lock ring may be disposed so as to engage the connection pipe at positions different from each other in the axial direction, or may be disposed so as to engage the connection pipe at positions opposite to each other.

However, the range of application of the connection pipe insertion confirmation mechanism used in the present invention is not limited to the type of pipe joint having the inner lock ring and/or the outer lock ring as described above. For example, the present invention is applicable to a pipe joint of a type including an outer cylinder concentrically arranged to form a housing portion to be fitted into a connection pipe and an inner cylinder extending from a joint body, and an annular lock ring having a plurality of teeth or claws radially extending to bite into an inner circumferential surface or an outer circumferential surface of the inner cylinder or an inner circumferential surface of the outer cylinder is fixed to the outer cylinder, and also to a pipe joint of a type including a cylindrical lock ring having protrusions such as teeth or claws for locking the connection pipe and movable in an axial direction between the concentrically arranged inner cylinder and the outer cylinder having a tapered surface reducing in diameter toward an insertion port. Further, if the outer cylinder and the inner cylinder form the housing portion of the connection pipe, the present invention can be applied to a pipe joint having no lock ring therein.

The pipe joint of the present invention preferably includes at least one seal ring for sealing a gap between the inner cylindrical body and the connection pipe on the outer circumferential surface of the inner cylindrical body and/or the inner circumferential surface of the outer cylindrical body. Generally, a groove portion is provided on the outer peripheral surface of the inner cylindrical body and/or the inner peripheral surface of the outer cylindrical body, and the seal ring is housed in the groove portion and fixed. The cross-sectional shape of the seal ring is not particularly limited, and seal rings having various cross-sectional shapes such as an O-shape, a square shape, a concave shape, and a lip shape can be used.

In particular, in the case of the pipe joint having the above-described inner lock ring and/or outer lock ring, as in the case of the pipe joint having the conventional movable lock ring or the pipe joint having the ring-shaped lock ring fixed inside, when the coupling pipe is inserted, the inner circumferential surface or the outer circumferential surface of the coupling pipe is hardly damaged by the claw portion of the lock ring, and thus a high sealing effect can be obtained.

According to another aspect of the present invention, there is provided a direct insertion type pipe joint comprising a joint body, an inner cylinder extending axially outward from the joint body, a through hole penetrating an inner and outer circumferential surfaces of the inner cylinder, and a groove extending axially inward from the through hole, an outer cylinder disposed outside the inner cylinder, a lock ring having a flexible rod-like member extending radially, the lock ring having a receiving portion for receiving a connection pipe inserted in the receiving portion, the lock ring being configured to prevent the connection pipe from coming off by pressing a projection having a tapered tip against an inner circumferential surface and/or an outer circumferential surface of the connection pipe, and is disposed movably in the axial direction in the housing portion, wherein the rod-like member is disposed to protrude from the through hole to the outside of the outer cylinder before the connection pipe is inserted, and when the connection pipe is inserted, the rod-like member is drawn in from the outside of the outer cylinder to be housed in the groove portion formed in the inner circumferential surface of the outer cylinder by pressing the insertion confirmation member into the axial inside side by the distal end portion of the connection pipe, and the insertion confirmation position of the connection pipe with respect to the housing portion length of the pipe joint can be freely changed by adjusting the length of the rod-like member of the insertion confirmation member.

In this type of one-piece pipe joint, flexible rod-like members radially extending from the C-ring-shaped or O-ring-shaped insertion confirmation member are disposed in the housing portion of the pipe joint so as to project outward from the through hole of the outer cylinder in an initial state before the insertion of the connection pipe. Therefore, normally, the insertion confirmation member connected to the rod-like member is disposed substantially directly below the through hole of the outer cylinder, and the length of the rod-like member can be adjusted to freely change the protruding length from the outer circumferential surface of the outer cylinder, so that the operator can easily confirm the initial state of the connection pipe before insertion.

On the other hand, when the connection pipe is inserted into the housing portion of the pipe joint, the insertion confirmation member occupies the entire or a part of the cross section of the housing portion, abuts against the tip end portion of the connection pipe, and is then pressed into the deepest portion of the pipe joint housing portion. At this time, since the rod-like member is connected to the insertion confirmation member, the rod-like member is press-fitted into the groove formed in the inner peripheral surface of the outer cylindrical body from the outside of the outer cylindrical body through the through hole and is accommodated in the groove along with the movement of the insertion confirmation member.

In this type of pipe joint, the length of the rod-like member inserted into the confirmation member portion may be adjusted to be substantially equal to the distance between the distal end position of the connection pipe and the through hole of the outer cylinder when the connection of the connection pipe is completed. Thus, when the inserted connection pipe reaches the position where the connection is completely completed, the rod-shaped members are all pulled into the through-holes from the outside of the outer cylindrical body or pulled into the groove formed in the inner circumferential surface of the outer cylindrical body through the through-holes, and are stored. In this way, the pipe joint of the present invention can freely change the insertion depth of the connection pipe with respect to the length of the housing portion of the pipe joint, that is, the insertion confirmation position of the connection pipe, by adjusting the length of the rod-shaped member of the connection pipe insertion confirmation mechanism.

Effects of the invention

According to the present invention, there is provided an in-line pipe joint having a dedicated pipe joint insertion confirmation mechanism, wherein a C-ring-shaped or O-ring-shaped member having a flexible rod-shaped member extending radially is disposed in a receiving portion of the pipe joint, and the length of the rod-shaped member is adjusted so that the ring-shaped member is pushed into the inside by the pipe joint when the pipe joint is inserted, and the rod-shaped member provided in advance in a through hole is pulled into the inside from the outside of an outer cylinder, thereby enabling the insertion confirmation position of the pipe joint with respect to the length of the receiving portion of the pipe joint to be freely changed.

As a result, the operator can visually and with fingers confirm the empty through hole of the outer cylinder, and can easily and accurately grasp whether or not the inserted connection pipe has reached a predetermined position with respect to the pipe joint, and whether or not the connection has been completed.

Drawings

Fig. 1 is a cross-sectional view of a pipe joint according to an embodiment of the present invention, the upper half of which shows a state before a connection pipe is inserted and the lower half of which shows a state after the connection pipe is inserted, the cross-section being cut along a central axis thereof;

FIG. 2 is a perspective view of an insertion confirmation member disposed in the housing of the embodiment of FIG. 1;

FIG. 3 is a perspective view of a sleeve mounted on the inner peripheral surface of the outer cylinder of the embodiment of FIG. 1;

fig. 4 is a perspective view of an insertion confirmation member of another embodiment;

FIG. 5 is a perspective view of a sleeve of other embodiments;

FIG. 6 is a perspective view showing the inner locking ring of the embodiment of FIG. 1;

FIG. 7 is a cross-sectional view of the inner locking ring of FIG. 6 in a cross-section through the central shaft;

FIG. 8 is a perspective view showing the outside locking collar of the embodiment of FIG. 1;

FIG. 9 is a cross-sectional view of the outer locking ring of FIG. 8 in a cross-section through the central axis;

fig. 10 is a cross-sectional view of a pipe joint according to another embodiment of the present invention, the upper half showing a state before insertion of a connection pipe and the lower half showing a state after insertion of the connection pipe, the cross-sectional view being cut along a cross-section passing through a center axis of the connection pipe.

Description of the symbols

1. 1' direct insertion type pipe joint

2 socket

3 connector body

30 passage opening part

31 front end part

4 inner cylinder

5 outer cylinder

50 through hole

51 center shaft

6 connecting pipe insertion confirming mechanism

7 sleeve

70 end of the tube

71 slit, groove part

8 insertion confirming member

80 insertion confirmation member body

81 Bar-shaped component

10 connecting pipe

11 inner side lock ring

110 bulge

111 slit

112 first outward claw portion

113 second outward claw part

12 outside lock ring

120 narrowing part

121 slit

122 first inward facing jaw

123 second inward claw

13 housing part

14 deepest part

15. 15' sealing ring

16. 16' groove part

17 fixed type outside lock ring

Detailed Description

Hereinafter, an inline pipe joint according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the following examples, and various modifications can be made without departing from the scope of the present invention.

[ examples ] A method for producing a compound

Example 1

Fig. 1 is a cross-sectional view showing a one-touch type pipe joint 1 according to a preferred embodiment of the present invention including a coupling pipe insertion confirmation mechanism 6, in which the upper half shows a state before a coupling pipe is inserted and the lower half shows a state after the coupling pipe is inserted, and the one-touch type pipe joint is cut in a cross section passing through a central axis thereof. As can be seen from fig. 1, the pipe joint 1 of the present invention is not limited to the I-shape as a whole, and may be T-shaped or cross-shaped, as long as it has at least one connection pipe insertion socket 2.

The pipe joint 1 includes a joint body 3, an inner cylinder 4, an outer cylinder 5, an inner lock ring 11, an outer lock ring 12, and a pipe insertion confirmation mechanism 6, and any of these components has a substantially cylindrical or annular shape. In addition, in embodiment 1, the joint main body 3 includes the inner cylinder 4 and is integrally formed by injection molding. The joint main body 3 and the inner cylindrical body 4 have passage openings 30 for flowing a fluid therein, and the tip end 31 thereof has a funnel shape to reduce resistance of the fluid. Further, when importance is attached to productivity, cost, and the like of the pipe joint 1, all the components of the joint main body 3, the inner cylinder 4, and the outer cylinder 5 may be integrally formed by injection molding or the like.

The connection tube insertion confirmation mechanism 6 used in example 1 is composed of a through hole 50 provided in the outer cylinder 5, a sleeve 7 attached to the inner circumferential surface of the outer cylinder 5, and an insertion confirmation member 8 disposed in the housing portion 13 formed by the outer cylinder 5 and the inner cylinder 4. The connection pipe insertion confirmation means 6 can easily and accurately confirm whether the inserted connection pipe 10 has reached a predetermined position in the pipe joint 1 and whether the connection of the connection pipe 10 is completed.

Fig. 2 is a perspective view of the insertion confirmation member 8 disposed in the housing portion 13. The insertion confirmation member 8 is composed of an O-ring-shaped insertion confirmation member main body 80 and a flexible rod-shaped member 81 extending radially from the main body. The rod-like member 81 is disposed in the housing portion 13 of the pipe joint 1 so as to protrude outward from the through hole 50 of the outer cylinder 5 in an initial state before the insertion of the connection pipe 10 (see the upper side of fig. 1). Therefore, the insertion confirmation member main body 80 connected to the rod member 81 is disposed substantially directly below the through hole 50 of the outer cylinder 5, and the length of the rod member 81 protruding from the outer circumferential surface of the outer cylinder can be freely changed by adjusting the length thereof, so that the operator can easily confirm the initial state of the connection pipe before insertion.

The through hole 50 provided in the outer cylinder 5 is not particularly limited in position, size, and shape as long as it is an opening penetrating the inner and outer circumferential surfaces of the outer cylinder 5. However, the position of through-hole 50 is determined in consideration of the insertion confirmation position of connection pipe 10 in pipe joint housing 13, the distance from deepest portion 14, the length of rod-like member 81 that should protrude from through-hole 50 in advance before the insertion of the connection pipe, and the like.

On the other hand, when connecting pipe 10 is inserted into receiving portion 13 of pipe joint 1, insertion confirmation member 8 occupies all or a part of the cross section of the receiving portion, abuts against the tip end portion of connecting pipe 10, and is then pushed into deepest portion 14 of pipe joint receiving portion 13. At this time, since the rod 81 is connected to the insertion confirmation member main body 80, the insertion confirmation member 8 is accommodated by being drawn into the groove (slit) 71 formed in the inner circumferential surface of the outer cylindrical body 5 from the outside of the outer cylindrical body 5 through the through hole 50 by the sleeve 7 (see the lower side of fig. 1).

In the connection tube insertion confirmation mechanism 6 used in example 1, the length of the rod-like member 81 may be adjusted to be substantially equal to the distance between the distal end position of the connection tube 10 when the connection of the connection tube 10 is completed and the through hole 50 of the outer cylindrical body 5. Thus, when the inserted connection pipe 10 reaches the position at which the connection is completely completed, the rod-like members 81 are all pulled into the through-holes 50 from the outside of the outer cylindrical body 5, or pulled into the groove portions 71 formed in the inner circumferential surface of the outer cylindrical body 5 by the sleeve 7 through the through-holes 50, and are stored (in fig. 1 and 10, the storage state of the rod-like members 81 is exaggerated, and the length of the rod-like members 81 shown in the drawings is shorter than necessary). Therefore, in pipe joint 1 of embodiment 1, the insertion depth of connecting pipe 10 with respect to the length of the receiving portion of pipe joint 1, that is, the insertion confirmation position of connecting pipe 10 can be freely changed by adjusting the length of rod-shaped member 81 of connecting pipe insertion confirmation mechanism 6.

As a result, the operator can visually and with his fingers, etc., check the through hole 50 of the outer cylinder 5 that is empty, and can easily and accurately grasp whether the inserted connection pipe 10 has reached a predetermined position with respect to the pipe joint 1, and whether the connection is complete.

In addition, in the present embodiment 1, in order to more reliably and easily confirm the inserted state of the connection pipe 10, the two rod members 81 are provided symmetrically with respect to the center of the insertion confirmation member main body 80, and therefore, the two through holes 50 are provided symmetrically with respect to the central axis 51 of the outer cylindrical body 5 in the outer cylindrical body 5 of the pipe joint 1 in accordance with the number and positions of the rod members 81.

The rod-like member 81 is accommodated in the groove portion 71 on the inner peripheral surface of the outer cylinder while being deformed in a bending manner in accordance with the movement of the insertion confirmation member 8 toward the inside in the axial direction. Therefore, the rod-like member 81 and the insertion confirmation member 8 including the same are preferably made of a material having flexibility and strong tensile stress resistance, and in example 1, made of a thermoplastic elastomer. The thermoplastic elastomer is generally less stretchable under a constant load than synthetic rubber or natural rubber, and is therefore suitable as a material for the rod-like member 81 that is required to be deformed in a bending manner while maintaining a length corresponding to the insertion confirmation position of the connection pipe 10.

In order to obtain high deformation characteristics of the rod-like member 81, the shape thereof may be modified to be easily bent, such as a flat shape in cross section. The rod-like member 81 of example 1 has a nearly hinged structure having a smaller cross-sectional area than the other portions, for example, by narrowing the cross-sectional area near the root of the insertion confirmation member main body 80 as shown in fig. 2 or by locally thinning the same as shown in fig. 4, and thus can obtain high bending characteristics at the initial stage of drawing.

Further, since the shape of the distal end portion of the rod-like member 81 and the like can be easily confirmed by the operator with a finger or the like, the shape may be formed into a shape that can stimulate the finger, such as a shape in which the distal end portion is tapered or a surface having irregularities (see fig. 4). In order to improve visibility, the rod 81 or the tip portion of the rod may be colored in a conspicuous color such as a fluorescent color.

Fig. 3 is a perspective view showing the sleeve 7 attached to the inner peripheral surface of the outer cylinder 5. The sleeve 7 has a cylindrical shape having an O-shaped cross section at an end 70 thereof, and has two slits 71 formed on a circumferential surface thereof so as to face each other and extending in the axial direction at positions corresponding to the through holes 50 of the outer cylinder 5. In example 1, the sleeve 7 is attached to the inner peripheral surface of the outer cylindrical body 5, and the groove portion 71 formed of a slit is formed from the through hole 50 toward the inside in the axial direction.

If the groove 71 is not formed in the inner peripheral surface of the outer cylindrical body 5, the following problems occur: the rod-like member 81 drawn into the housing portion 13 with the insertion of the connection pipe 10 is sandwiched between the inner circumferential surface of the outer cylinder 5 and the outer circumferential surface of the connection pipe 10, and hinders the further insertion of the connection pipe 10 or is crushed (lead きちぎゐ).

Further, as the space provided between the inner peripheral surface of the outer cylindrical body 5 and the outer peripheral surface of the connection pipe 10 for drawing in the rod-like member 81, a separate groove portion 71 is formed, not by utilizing a clearance portion generated by a diameter difference between the inner diameter of the outer cylindrical body 5 and the outer diameter of the connection pipe 10. The reason is that: if the gap is used, the gap between the inserted connection pipe 10 and the outer cylinder 5 may be fluctuated (ricketty), and the connection pipe 10 may not be firmly fixed.

Therefore, in the present embodiment 1, the inner diameter of the outer cylinder 5 is set larger than the outer diameter of the connection pipe 10, and by installing the sleeve 7 therein, the inner peripheral surface having the inner diameter substantially the same as the outer diameter of the connection pipe 10 is formed. In addition, in view of the ease of attachment of the sleeve 7, the sleeve 7 is formed into a C-shape having a partially notched cross section as shown in fig. 5 so that the outer diameter thereof can be deformed to a small extent.

The use of the sleeve 7 can improve the formability of the outer cylinder 5 and the mountability of internal parts such as the insertion confirmation member 8 and the outer lock ring 12. In particular, in the case of the pipe joint 1 of the type using the outer lock ring 12 described later, the fixing wall 72 parallel to the radial direction for restricting the axial movement of the outer lock ring 12 is easily formed on the inner peripheral surface of the outer cylinder 5, which is convenient.

Referring again to fig. 1, in the housing portion 13 of the pipe joint 1 of this embodiment 1, there are disposed an inner locking ring 11 and an outer locking ring 12 movable in the axial direction, the inner locking ring 11 and the outer locking ring 12 having a first claw portion for pressing the inner and outer peripheral surfaces thereof when the connection pipe is inserted and a second claw portion for catching the connection pipe when the connection pipe is pulled out. However, in embodiment 1, it is not necessary to attach the lock ring to both the outer peripheral surface of the inner cylinder 4 and the inner peripheral surface of the outer cylinder 5, and it is sufficient to attach the lock ring to either one. However, considering that one lock ring may be damaged by dropping of the pipe joint 1, adhesion of a solvent, stepping, or the like, it is preferable to attach the lock ring to both the inner cylinder 4 and the outer cylinder 5 as in example 1.

Further, since the inner lock ring 11 and the outer lock ring 12 which are movable in the axial direction are disposed on the outer peripheral surface of the inner cylinder 4 and the inner peripheral surface of the outer cylinder 5 of the pipe joint 1, a radially parallel fixed wall and a tapered wall which continuously expands or reduces the diameter toward the outside in the axial direction are formed. Therefore, one end (fixed end) of the inner lock ring 11 and the outer lock ring 12 is substantially restricted from moving in the axial direction due to the relationship with the fixed wall of the inner cylinder 4 or the outer cylinder 5, and the other end (free end) of the inner lock ring 11 and the outer lock ring 12 is fitted between the fixed wall and the tapered wall and allows for movement in the axial direction due to the relationship with the tapered wall.

Fig. 6 and 7 are a perspective view of the inner lock ring 11 used in the pipe joint 1 of the present embodiment and a cross-sectional view of the pipe joint when the pipe joint is cut along a cross-section passing through the center axis.

The inner lock ring 11 disposed on the outer peripheral surface of the inner cylinder 4 is formed of a cylindrical body, and a plurality of slits 111 are cut from the end of the cylindrical body to form the free end of a cantilever (cantilever). Further, the inner lock ring 11 includes: a first outward claw 112 for pressing the inner peripheral surface of the connection pipe by elastic deformation when the connection pipe is inserted, and a second outward claw 113 disposed at the free end for locking the connection pipe when the connection pipe is pulled out.

The pressing function of the first outward claw portion 112 is realized by making the structure of the inner lock ring itself of the claw portion that supports the inner lock ring 11 an elastically deformable structure. That is, since the axial cross-sectional shape of the bulging portion 110 of the inner lock ring 11 has a shape like an inchworm (refer to fig. 1), it is bent when pressed radially inward, and the inner peripheral surface of the inserted connection pipe 10 is appropriately pressed by the reaction force thereof. Further, since the slit 111 extends in the axial direction so as to penetrate the body portion of the inner lock ring 11, the respective bulging portions 110 divided by the slit 111 do not interfere with each other, and elastic deformation is easy.

As a result, in pipe joint 1 of the present embodiment, when connecting pipe 10 is inserted into a predetermined position in receiving portion 13 of pipe joint 1 and then moved in the drawing direction, first outward claw portion 112 is engaged with the inner peripheral surface of connecting pipe 10, and inner lock ring 11 is also moved in the drawing direction together with connecting pipe 10. The free end of the inner lock ring 11 enters the tapered wall region of the inner cylinder 4, and the inner lock ring 11 expands in diameter by the interaction with the tapered wall so that the second outward claw portions 113 are pressed against the inner circumferential surface of the connection pipe 10, and the connection pipe 10 is securely and firmly locked by the second outward claw portions 113.

On the other hand, fig. 8 and 9 show a perspective view and a cross-sectional view of the outer lock ring 12 used in the pipe joint 1 of the present embodiment when the pipe joint is cut along a cross-section passing through the center axis.

The outer lock ring 12 disposed on the inner peripheral surface of the outer cylinder 5 is formed of a cylindrical body, as with the inner lock ring 11, and a body portion thereof is formed with a plurality of slits 121 cut from an end portion of the cylindrical body to form a free end of a cantilever (cantilever). Further, the outer lock ring 12 includes: a first inward claw 122 for pressing the outer peripheral surface of the connection pipe by elastic deformation when the connection pipe is inserted, and a second inward claw 123 disposed at the free end for locking the connection pipe when the connection pipe is pulled out.

The pressing function of the first inward claw portion 122 is realized by making the structure of the outer lock ring itself that supports the claw portion of the outer lock ring 12 an elastically deformable structure. That is, since the axial cross-sectional shape of the narrowed portion (recessed portion) 120 of the outer lock ring 12 is like an inchworm (refer to fig. 1), it is bent when being pressed radially outward, and the outer peripheral surface of the inserted connection pipe 10 is appropriately pressed by the reaction force thereof. Further, since the slit 121 extends in the axial direction so as to penetrate the body portion of the outer lock ring 12, the respective constricted portions 120 divided by the slit 121 do not interfere with each other, and elastic deformation is easy.

As a result, in pipe joint 1 of the present embodiment, when connecting pipe 10 is inserted into a predetermined position in receiving portion 13 of pipe joint 1 and then moved in the drawing direction, first inward claw portion 122 is engaged with the outer peripheral surface of connecting pipe 10, and outer lock ring 12 is also moved in the drawing direction together with connecting pipe 10. The free end of the outer lock ring 12 enters the tapered wall region of the outer cylinder 5, and the outer lock ring 12 is reduced in diameter by the interaction with the tapered wall so that the second inward claw portions 123 are pressed against the outer peripheral surface of the connection pipe 10, and the connection pipe 10 is securely and firmly locked by the second inward claw portions 123.

The material of the lock rings 11 and 12 that can achieve the above-described function is not particularly limited as long as it is a hard material having appropriate elasticity, and it can be molded from a plastic material or a metal material. In particular, when the resin is molded from a plastic material, an engineering plastic material such as polyphenylene sulfone (PPSU) resin or polyphenylene sulfide (PPS) resin is preferably used as the material.

The pipe joint 1 of the present embodiment includes two seal rings 15 and 15' (see fig. 1) for sealing a gap with the connection pipe 10 on the outer peripheral surface of the inner cylindrical body 4. The seal rings 15 and 15 'are fixed by providing groove portions 16 and 16' on the outer peripheral surface of the inner cylindrical body 4 and housing them therein. The cross-sectional shape of the seal ring is not particularly limited, and seal rings 15 and 15' having an O-shaped cross section are used in example 1.

The seal ring may be disposed on the outer peripheral surface of the inner cylindrical body 4 or the inner peripheral surface of the outer cylindrical body 5, or on both peripheral surfaces thereof. However, in the case of the pipe joint 1 of embodiment 1, the seal rings 15 and 15' are disposed on the outer peripheral surface of the inner cylindrical body 4 in order to eliminate the influence of dirt or dust entering from the outside as much as possible and to maintain a sealed state even when the outer cylindrical body 5 is damaged for some reason. The arrangement of the seal rings 15 and 15' also serves to prevent corrosion of metal portions exposed at the end surfaces when a round pipe such as an aluminum triple-layer pipe is connected to the pipe joint 1.

Further, by disposing the seal ring 15 at a position facing the second inward claw portion 123 of the outer lock ring 12 as in embodiment 1, a stronger sealing effect can be obtained by the pressure contact force of the second inward claw portion 123 after the connection pipe is attached. In addition, in order to reduce the backlash of the attached connection pipe 10, the seal rings 15, 15' of the present embodiment are disposed apart in front and rear thereof in such a manner that the same-side inner lock ring 11 is attached therebetween.

[ example 2 ]

Fig. 10 is a cross-sectional view showing a state before the connection pipe is inserted in the upper half and a state after the connection pipe is inserted in the lower half, and showing a case where the connection pipe is cut in a cross section passing through the central axis thereof, in an inline type connection pipe 1' according to another preferred embodiment of the present invention including a connection pipe insertion confirmation mechanism 6. As understood with reference to fig. 10, the pipe joint 1' of the present embodiment 2 has the same configuration as the pipe joint 1 of the embodiment 1 except for the following points: the lock ring 17 for locking the connection pipe 10 has a plurality of radially extending teeth or claws, and is a ring-shaped lock ring fixed to the inner circumferential surface of the outer cylinder 5.

Therefore, the pipe joint 1' of the present embodiment 2 includes the joint body 3, the inner cylinder 4, the outer cylinder 5, the fixed-type outer lock ring 17, and the joint pipe insertion confirmation mechanism 6, and any of the components has a substantially cylindrical or annular shape. In addition, in embodiment 2, the joint main body 3 includes the inner cylinder 4 and is integrally formed by injection molding. The joint body 3 and the inner cylindrical body 4 have passage openings 30 for fluid flow therein, and the tip end 31 thereof has a funnel shape to reduce resistance to fluid flow. Further, when importance is attached to the productivity, cost, and the like of the pipe joint 1', all the components of the joint main body 3, the inner cylinder 4, and the outer cylinder 5 may be integrally molded by injection molding or the like, as in the case of the pipe joint 1 of embodiment 1.

In the pipe joint 1' of example 2, the connection pipe insertion confirmation mechanism 6 of the connection pipe 10 is constituted by the through hole 50 provided in the outer cylinder, the sleeve 7 attached to the inner peripheral surface of the outer cylinder 5, and the insertion confirmation member 8 disposed in the housing portion 13 formed by the outer cylinder 5 and the inner cylinder 4, as in the case of the pipe joint 1 of example 1. Therefore, in the pipe joint 1' of embodiment 2, the functions and configurations of the components other than the fixed-type outside locking ring 17 are the same as those of the pipe joint 1 of embodiment 1, and therefore, detailed descriptions of the functions and configurations of the components are omitted here.

In the pipe joint 1 'of embodiment 2, as shown in the upper half of fig. 10, before the connection pipe 10 is inserted into the housing portion 13 of the pipe joint 1', the rod-like member 81 of the O-ring-shaped insertion confirmation member 8 is arranged to protrude from the through hole 50 to the outside of the outer cylinder 5. Further, the operator can easily and reliably grasp that connection pipe 10 and pipe joint 1' are not yet connected in a complete state by confirming the presence of rod 81 from the outside with the eyes, fingers, or the like.

On the other hand, when connection pipe 10 is inserted into deepest portion 14 of receiving portion 13 of pipe joint 1' and connection and fixing of connection pipe 10 is completed, insertion confirmation member 8 occupies the entire or a part of the cross section of receiving portion 13, abuts against the tip end portion of connection pipe 10, and is then pressed into deepest portion 14 of pipe joint receiving portion 13. At this time, since the rod 81 is integrally connected to the insertion confirmation member main body 80, the rod 81 is press-fitted into the groove (slit) 71 formed in the inner circumferential surface of the outer cylindrical body 5 by the sleeve 7 from the outside of the outer cylindrical body 5 through the through hole 50 and is accommodated in the groove as the insertion confirmation member 8 moves.

As a result, the operator can visually and visually confirm the empty through hole 50 of the outer cylinder 5 with his/her fingers, and can easily and accurately grasp whether the inserted connection pipe 10 has reached a predetermined position with respect to the pipe joint 1' and whether the connection is completed.

Claims

1. A pipe joint having a joint body, an outer cylinder and an inner cylinder forming a housing part for housing a connection pipe, and a connection pipe insertion confirmation mechanism for confirming an insertion state of the connection pipe,

the insertion confirmation mechanism is composed of the following parts:

a through hole penetrating the inner circumferential surface and the outer circumferential surface of the outer cylinder;

a groove portion formed on an inner peripheral surface of the outer cylinder and extending from the through hole to an inside in an axial direction; and

a C-shaped annular or O-shaped annular insertion confirmation member having a flexible rod-like member extending radially and disposed movably in the housing portion in the axial direction,

the rod-like member is disposed so as to protrude from the through hole to the outside of the outer cylinder before the connection pipe is inserted, and is drawn in from the outside of the outer cylinder to be accommodated in the groove formed in the inner circumferential surface of the outer cylinder by pushing the insertion confirmation member into the axial inner side from the distal end portion of the connection pipe when the connection pipe is inserted.

2. The pipe coupling according to claim 1,

by adjusting the length of the rod-like member of the insertion confirmation member, the insertion confirmation position of the connection pipe with respect to the length of the receiving portion of the pipe joint can be freely changed.

3. A pipe-fitting according to claim 1 or 2,

the groove portion is formed by attaching a sleeve having a slit extending in an axial direction to an inner peripheral surface of the outer cylinder.

4. A pipe-fitting according to claim 1 or 2,

the rod-like member has a flat shape in cross section.

5. A pipe-fitting according to claim 1 or 2,

the insertion confirmation member is molded from a thermoplastic elastomer, a synthetic rubber, or a natural rubber.

6. A pipe-fitting according to claim 1 or 2,

the outer circumferential surface of the inner cylinder or the inner circumferential surface of the outer cylinder is provided with a seal ring for sealing a gap between the outer circumferential surface of the inner cylinder or the inner circumferential surface of the outer cylinder and the connection pipe.

7. A pipe-fitting according to claim 1 or 2,

the pipe joint further comprises the inner cylinder and an inner lock ring,

the inner cylinder body is also provided with a fixed wall parallel to the radial direction and a conical wall continuously expanding diameter towards the axial outer side on the outer circumferential surface,

the inner locking ring is a cylindrical body having a plurality of slits for forming a free end of a cantilever beam, and has a first outward claw portion that presses an inner peripheral surface of the connection pipe by elastic deformation of the cylindrical body when the connection pipe is inserted, and a second outward claw portion that is disposed at the free end and that engages the connection pipe when the connection pipe is pulled out, and the inner locking ring is disposed so as to be movable in an axial direction between a fixed wall and a tapered wall of the inner cylindrical body,

when the connection pipe is inserted into the receiving portion at a predetermined position and moved in a drawing direction, the inner lock ring is engaged with an inner peripheral surface of the connection pipe by the first outward claw portion and moved in the drawing direction together with the connection pipe, a free end of the inner lock ring enters a tapered wall region of the inner cylinder, and then the inner lock ring is expanded in diameter by an interaction with the tapered wall so as to press the second outward claw portion against the inner peripheral surface of the connection pipe.

8. A pipe-fitting according to claim 1 or 2,

the pipe joint further comprises the outer cylinder and an outer lock ring,

the inner circumferential surface of the outer cylinder body is also provided with a fixed wall parallel to the radial direction and a conical wall continuously reducing the diameter towards the outer side in the axial direction,

the outer locking ring is a cylindrical body having a plurality of slits for forming a free end of a cantilever beam, and has a first inward claw portion that presses an outer peripheral surface of the connection pipe by elastic deformation of the cylindrical body when the connection pipe is inserted, and a second inward claw portion that is disposed at the free end and that engages the connection pipe when the connection pipe is pulled out, and the outer locking ring is disposed so as to be movable in an axial direction between a fixing wall and a tapered wall of the outer cylindrical body,

when the connection pipe is inserted into the predetermined position of the receiving portion and moved in the drawing direction, the outer lock ring is engaged with the outer peripheral surface of the connection pipe by the first inward claw portion and moved in the drawing direction together with the connection pipe, and the free end of the outer lock ring enters the tapered wall region of the outer cylinder and then is reduced in diameter by the interaction with the tapered wall so as to press the second inward claw portion against the outer peripheral surface of the connection pipe.

9. A pipe-fitting according to claim 1 or 2,

the pipe joint also comprises the inner cylinder, the outer cylinder, an inner locking ring and an outer locking ring,

when the connection pipe is inserted into a predetermined position of the housing part and then moved in a drawing direction, the inner lock ring is engaged with an inner circumferential surface of the connection pipe by the first outward claw portion to move in a drawing direction together with the connection pipe, a free end of the inner lock ring enters a tapered wall region of the inner cylinder, then, the inner locking ring is expanded in diameter by the interaction with the tapered wall so as to press the second outward claw portion against the inner peripheral surface of the connection pipe, and the outer lock ring is engaged with the outer circumferential surface of the connection pipe by the first inward claw portion to move in the drawing direction together with the connection pipe, and a free end of the outer lock ring enters a tapered wall region of the outer cylinder, the outer locking ring is then reduced in diameter by interaction with the tapered wall so as to press the second inward claw portion against the outer peripheral surface of the connection pipe.

10. A pipe joint is characterized in that a pipe joint body is provided,

which is composed of a joint body, an inner cylinder, an outer cylinder, a lock ring and a C-shaped annular or O-shaped insertion confirmation part,

the inner cylinder extends axially outward from the fitting body,

the inner peripheral surface of the outer cylinder has a through hole penetrating the inner and outer peripheral surfaces and a groove extending from the through hole to the inside in the axial direction, the outer cylinder is disposed outside the inner cylinder, and a housing portion for housing a connection pipe is formed between the outer cylinder and the inner cylinder,

the locking ring prevents the connection pipe from falling off by pressing the protrusion with a sharp front end against the inner and/or outer circumferential surface of the connection pipe inserted into the containing part,

the insertion confirmation member has a flexible rod-like member extending radially and is disposed movably in the housing portion in the axial direction,

the rod-like member is arranged to protrude from the through hole to the outside of the outer cylinder before the connection pipe is inserted, and is drawn in from the outside of the outer cylinder to be accommodated in the groove formed in the inner circumferential surface of the outer cylinder by pushing the insertion confirmation member into the axial inner side from the distal end portion of the connection pipe when the connection pipe is inserted, and the insertion confirmation position of the connection pipe with respect to the length of the accommodation portion of the pipe joint can be freely changed by adjusting the length of the rod-like member of the insertion confirmation member.