JP2001132881A - Bell-and-spigot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To positively seal a bellows pipe and to prevent the bellows pipe from slipping of by compressing a packing and pressing a slip-off preventing member by a spring released from the compressed state only by inserting the bellows pipe in a joint body. SOLUTION: This bell-and-spigot pipe joint comprises, inside a joint body, a spring 30 sprung in an axial direction, a guide 20 for holding the spring 30 in the compressed state, and a packing 41 compressed by the elongation of the spring 30. The packing 41 is compressed by releasing the compression holding state of the spring 30 by a bellows pipe 40 inserted in the joint body, and further a pipe 40 is locked in the slip-off prevented state. The spring holding member 20 has an annular part 22 for receiving one end of the spring 30; a locking piece 21 extending to the inner part in the axial direction; a projecting part 23 locked to an inner surface recess 15 of the joint body; and an abutting part 24 abutting on the end part of the pipe 40. The spring holding member 20 is locked to the recessed groove 15 provided in the joint body, and the lock state is released being pressed by the end part of the bellows pipe 40. A soft packing or a lip packing is used as the packing 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plug-in type pipe joint having good sealing properties, and more particularly to a plug-in type pipe capable of providing good sealing properties and preventing falling off simply by inserting a bellows pipe into a joint body. It relates to a joint.

[0002]

2. Description of the Related Art Conventionally, for example, Utility Model Publication No. 25654
No. 69 discloses a socket having a connection hole into which a flexible tube is inserted as shown in FIG. 11, a fastening member screwed into an open end of the socket, and a fastening member screwed into the socket. A substantially C-shaped positioning member mounted between both ends of the socket and the tightening member to be positioned in the socket, and the inner peripheral surface is formed radially inside the connection hole of the socket so as to correspond to the outer peripheral surface of the flexible tube. A plurality of retainers, and a holding member for elastically holding the plurality of retainers such that the inner diameter is enlarged and reduced. After the flexible pipe is inserted between the plurality of retainers, the positioning member is removed and the tightening member is tightened. There is a flexible pipe joint in which the retainer is pressed toward the bottom of the connection hole to fix the flexible pipe to the socket.

[0003]

In the above conventional flexible pipe joint, after inserting the flexible pipe into the connection hole, the positioning member is removed, and then the tightening member is tightened to the socket using a tool, and the flexible pipe is inserted into the socket. Fixed to. However, there is still a work of tightening using a tool, and there is a problem that after the flexible tube is inserted, the tightening is forgotten and leakage occurs. In addition, it takes time to remove the positioning member and cannot be easily connected. Further, an elastic holding member for holding a plurality of retainers is required, and the structure is complicated. The present invention overcomes the above-mentioned problems and compresses the packing simply by inserting the flexible bellows tube into the joint to securely seal the packing. It provides a simple and safe structure of a bellows pipe plug-in fitting that has a leak prevention performance in the event of a fire and that can reliably perform leak inspection confirmation when there is a hole in the bellows pipe due to nailing. is there.

[0004]

SUMMARY OF THE INVENTION The gist of the present invention is a joint for mounting a packing in a joint body and sealing the pipe inserted in the joint body, wherein the packing uses a soft low-hardness rubber packing. It is a plug-in type pipe joint characterized by the following. A plug-in type pipe joint characterized in that a soft low-hardness rubber packing is mounted in a joint body, and the outer peripheral surface is sealed with a bellows tube having a corrugated uneven portion. In the above, the packing is a low-hardness rubber packing having a JIS Japanese Industrial Standard A hardness of 25 degrees or less, and is compressed between the connecting pipe inserted into the joint body, adapted to the outer peripheral surface of the pipe, and sealed. It is a plug-in type pipe joint.

[0005] Further, a spring resilient to the entrance side in the axial direction of the main body mounted in the joint main body, and a spring locked in the joint main body to hold the spring in a compressed state, and a connecting bellows tube is inserted into the joint main body. A guide from which the engagement with the joint body is released at the end of the bellows tube, and a packing which is released from the lock of the guide and is compressed on the outer peripheral surface of the bellows tube by expanding a compressed spring. It is a retaining member which is pushed through the packing by the extension of the spring and is engaged with the corrugated crests of the bellows tube. The stopper is inserted into the joint body to seal and prevent the bellows tube from coming off. A plug-in type pipe joint characterized in that: As the packing, a low-hardness rubber packing having a hardness of 25 degrees or less according to JIS Japanese Industrial Standard A can be used.

In the above, the guide has an annular flange portion that receives one end of the spring and presses the packing on the back surface, and a locking portion that extends from the annular flange portion to the axially deep portion of the main body and locks with the joint main body. The locking portion locks into a groove provided in the joint body to hold the spring in a compressed state, and the insertion of the bellows tube pushes the locking portion of the guide so that the groove is formed. A plug-in type pipe joint characterized in that it is released from the engagement with the pipe joint. In the above, the retaining member has an annular locking portion having one end locked in the joint main body and the other end having a split groove in an axial direction. A pivot portion which is engaged with the bellows tube by extension of the spring, whereby the outer peripheral surface of the pivot portion is pushed through the packing to reduce the diameter of the pivot portion and engage with the bellows tube. It is a joint.

[0007] In the above, the retaining member is an expandable and contractible annular coil ring having a metal coil formed in an annular shape, one end of which is locked in the joint body, and the spring is extended to allow the annular coil ring and the packing to move between the annular coil ring and the packing. A plug-in type pipe joint characterized in that the annular coil ring is reduced in diameter via a spacer that presses the outer peripheral surface of the annular coil ring attached to the bellows tube, and is engaged with the corrugated ridges of the bellows tube. In the above, the retaining member is an expandable and contractable C-shaped ring having a notch in a part of an annular shape, one end of which is locked in the joint body, and the C-shaped ring and the packing are formed by extension of the spring. Through a spacer that presses the outer peripheral surface of the C-shaped ring mounted between
A plug-in type pipe joint characterized in that a U-shaped ring is reduced in diameter and is locked to a corrugated peak portion of a bellows tube.

In the above, the packing is a U-shaped packing having an annular concave groove in the axial direction, and the guide is formed on the back surface of the annular flange portion so as to enter the concave groove of the packing and expand the concave groove. A plug-in type pipe joint characterized in that the insertion part of the guide pushes and expands the concave groove of the packing and seals with the bellows tube by extension of the spring. In the above, there is provided a plug-in type pipe joint in which a refractory expansion packing which expands in volume by heat is mounted in the joint body. In the above, at the end inside the joint body, a watertight packing for sealing with the resin coating layer on the outer peripheral surface of the bellows pipe is mounted, and between the watertight packing and the packing mounting portion, gas permeates from the inside to the outside, but solid or A plug-in type pipe fitting characterized by mounting a selectively permeable member that does not transmit liquid.

[0009]

According to the present invention, the low-hardness rubber packing is easily deformed and adapts well to the outer peripheral surface shape of the pipe.
Good sealing properties can be obtained even with a small compression force.
The normal rubber packing hardness is about 50 degrees in JISA hardness, but in the present invention, the packing is particularly gel-like by using a hardness of 25 degrees or less, so that even if there is a flaw on the pipe surface, it is good on the pipe surface. Good sealing properties are obtained. In particular, in the case of a bellows tube in which the outer peripheral surface of the tube has corrugated irregularities, the packing is easily deformed due to the insertion of the bellows tube, so that the tube can be easily inserted, and the sealability that conforms well to the corrugated irregularities of the bellows tube. Good.

In the pipe joint according to the third aspect, when the bellows pipe is inserted into the joint body, the guide holding the spring in a compressed state is released from the engagement with the joint body and is compressed in the axial direction. The spring extends toward the connection port. The guide is pushed to the end connection port side by the extension of the spring to compress the packing, and the retaining member is pressed and the retaining member is locked to the corrugated uneven portion of the bellows tube. At the same time, the watertight packing seals the inserted bellows tube to prevent external water from entering the joint body. Therefore, the spring pushes the guide to the entrance side only by inserting the connecting pipe, and the guide presses the packing and the retaining member into the joint body, whereby the connection is performed. If the bellows tube is not completely inserted, the spring does not expand, so that the packing and the retaining member are not compressed, so that there is no halfway connection state and the tube can be reliably connected. At the same time, when the guide holding the spring in the compressed state is released from the engagement with the joint body, an unlocking sound is generated by the extension of the spring outside the joint, so that the bellows tube reaches a regular position in the joint body. To check if the connection is correct.

[0011] For this reason, packing is mounted in the concave and convex groove of the bellows tube in the related art, and the packing and disengagement are not performed by the sealing or retaining action of merely abutting against the inner surface of the joint, but by the extension of the spring holding the compressive force in the joint. Since the stopper member is pressed and compressed, a reliable sealing effect and a retaining function are achieved. The packing is made of soft low-hardness rubber with a hardness of 0 to 25 degrees in JIS Japanese Industrial Standard A. When the packing is compressed in the axial direction by the extension of the spring, it follows the uneven surface of the bellows tube in the axial direction and deforms. It fits well and provides a secure seal. The retainer can be a retainer that pivots at one end and engages the uneven surface of the bellows tube or an expandable and contractible coil spring with an annular metal coil ring. The spacer attached to the pusher pushes the stopper, and the stopper is locked to the uneven portion on the outer peripheral surface of the bellows tube.

Further, by using a U-shaped packing having a concave groove in the axial direction and providing an annular entrance portion which enters the concave groove of the packing at the end of the guide annular portion, the guide of the guide is extended by extension of the spring. The entry part enters the groove of the packing,
Since the packing is pushed and expanded securely in the direction perpendicular to the axis, the packing is compressed on the surface of the bellows tube, and the sealing is reliably performed.
By installing a refractory packing that expands in volume due to heat in the joint body, a sealing action in the event of a fire is performed. Furthermore, by installing a selectively permeable member that transmits gas from the inside to the outside but does not transmit solids and liquids between the packing mounting portion and the watertight packing mounting portion of the joint body, the bellows tube has a hole or the like. At this time, the gas in the pipe enters the joint through the resin coating layer coated on the surface of the bellows tube and the outer peripheral surface, and this gas passes through the selectively permeable member and is ejected to the outside. After that, by bringing the gas leak detector close to the joint portion, it is possible to easily detect a hole defect in the bellows tube. In addition, since the permselective member does not transmit solids or liquids, for example, external corrosive water does not enter the joint, thereby preventing corrosion inside the joint.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a longitudinal sectional view showing a state before connection with a pipe 40. A joint main body 10 is screwed together with a main body 11 and a nut-shaped main body 12, and is integrally provided in an airtight manner via an O-ring. The main body 10 has an insertion port 14 at the entrance side and a through-hole 19 at the center, and has a step 13 between them, and the bellows tube 40 inserted from the entrance side abuts. A refractory packing 4 containing expanded graphite, which expands in volume by heat, is provided on the step portion 13.
In the event of a fire, the refractory packing 49 expands due to heat to ensure a seal with the pipe 40. A concave groove 15 for locking the guide 20 is provided on the inner surface at the back of the insertion opening 14, and the guide 20 shown in FIG.
The locking projection 23 provided on the locking piece 21 is locked, and the coil spring 30 is held in a compressed state by the annular portion 22. The inner surface of the end is a contact portion 24 that contacts the inserted tube 40. A plurality of locking pieces 21 protrude from the annular portion 22, and locking projections 23 are formed on the outer surface thereof so as to lock into the concave grooves 15 of the joint body.
And a contact portion 24 that is inclined from the locking convex portion 23 and contacts the end of the connection pipe 40.

As shown in FIG. 2, an abutting portion 2 is formed at the end of the bellows tube 40.
4 is pressed, the locking piece is brought into contact with the contact portion 24 by leverage principle.
Is bent in the horizontal direction, the outer diameter of the locking projection 23 provided on the locking piece 21 is reduced, and is released from locking with the concave groove 15 as shown in FIG. When released from the engagement with the concave groove 15, the coil spring 30 expands, the guide 20 moves to the connection port entrance side, and the annular portion 22 pushes the packing 41 mounted on the opposite side. 32 is pushed to the entrance side. In particular, the packing 41 is soft and easily deformed by the pressing force of the spring.
A low hardness rubber having a hardness of 0 to 25 degrees is used. The packing 41 is a soft rubber that is close to a gel, and is a soft packing that can be easily deformed by touching only with a hand.

As shown in FIG. 5, the spacer 32 has an inner surface having a tapered inner surface 33 which expands toward the entrance, and the tapered inner surface 33 pushes against the tapered outer surface of the retainer 35 which is locked to the main body 11, and The distal end locking portion 36 is reduced in diameter and locked in the concave groove on the outer surface of the inserted bellows tube 40, so that the tube 40 is prevented from coming off. As shown in FIG. 6, the retainer 35 has a ring shape at its base end and an annular groove 37 on the outer peripheral surface which is engaged with the main body 11. 38 are provided, and the whole is made of a copper alloy and a resin to have elasticity.

A watertight packing 43 is mounted on the inner surface of the end of the joint body and hermetically sealed with the resin coating layer 44 on the outer surface of the inserted bellows tube 40 to prevent corrosive water from entering the joint from outside the joint. I have. A through-hole 51 is provided in a part of the circumference between the mounting portions of the packing 41 and the watertight packing 43, and a selectively permeable member that transmits gas from the inside to the outside but does not transmit solids and liquids through the through-hole 51. 50 (trade name Sunmap) is attached. Since the gas permeates through the joint from the inside to the outside of the joint, if the gas leaks due to a hole made in the bellows tube 40 by nailing or the like, a resin coating is applied to the surface of the metal bellows tube 40 and the outer surface of the tube. The gas in the tube 40 enters between the layers 44 and enters the joint, and the gas permeates through the permselective member 50 and is ejected to the outside of the joint. For this reason, by making the gas leak detector close to the joint connection portion after piping the bellows tube 40, it is possible to easily detect a hole defect in the bellows tube 40 and prevent a gas accident beforehand. In addition, since the permselective member 50 does not transmit solids and liquids, for example, external corrosive water does not enter the joint, thereby preventing corrosion inside the joint.

FIGS. 7 to 10 show a second embodiment of the present invention. The same parts as those in the first embodiment are the same and will not be described. FIG. 7 shows a state before the tube is inserted. In this embodiment, the structure of the packing pressing portion of the packing 45 and the guide 27 and the shape of the locking member 55 with the tube are different from those of the first embodiment. A letter-shaped lip packing 45 is used. As shown in FIG. 8, the tube 40 is inserted, and the locking projection 23 of the guide 27 is inserted into the groove 15 of the main body.
Is released from the engagement of the coil spring 30, the annular contact portion 26 of the guide 27 fits into the annular portion of the lip concave portion 47 of the packing 45, and the inner and outer surfaces of the packing 45 are expanded. As a result, the inner peripheral portion 46 of the lip packing 45 is pressed against the outer surface of the bellows tube 42, and the outer peripheral portion 48 is pressed against the inner peripheral surface of the joint, thereby securely sealing.

The guide 27 is shown in FIG. 9. The annular contact portion 26 of the guide 27 is provided in a wedge shape with a tapered cross section.
And the spacer 32 is pressed together with the packing 45 by the pressing force of the coil spring 30, and the tapered inner surface 33 of the spacer 32 makes the outer surface of the C-ring shaped locking member 55 attached to the locking step 16 of the main body. Press to reduce the diameter of the locking member 55. The locking member 55 is locked in the concave groove of the bellows tube 40, and the bellows tube 40 is prevented from falling off with the step 16.

In this embodiment, the annular contact portion 26 of the guide 25 enters the lip concave portion 47 of the packing due to the extension of the coil spring 30 and pushes the inner and outer peripheral surfaces of the packing 47 to expand. The inner peripheral surface can be reliably compressed and sealed, and the bellows tube 40 can be prevented from coming off, so that a reliable seal connection can be made. The retaining member 55 shown in the present embodiment may be the retainer 35 shown in FIG. 6 of the above embodiment, and another metal coil is provided on an annular coil ring which can be expanded and contracted to engage with the bellows tube concave groove. You may make it stop. Further, instead of the coil spring 30, a disc spring may be used, or a rubber member having elasticity may be used.

[0020]

As described above, in the pipe joint of the present invention, particularly, since a soft packing is attached, the pipe fitting is well adapted to the surface of the pipe and absorbs irregularities such as scratches on the pipe surface, so that the sealing property is good. In addition, since it is easily deformed even with a small compressive force, it is excellent as a seal packing for a bellows tube, furthermore, it is easy to insert the bellows tube into a joint body, and it is excellent as a plug-in type pipe joint for a bellows tube. . When the bellows tube is inserted into the joint body, the holding state of the spring held in a compressed state in the joint body is released, the spring expands, the packing is compressed in the joint body, and the seal with the bellows tube is achieved. In addition, when the compressed state of the spring is released, a release sound is emitted to the outside, so that it is possible to reliably insert the bellows tube and check whether the connection is securely performed. In addition, if the bellows tube is not completely inserted, the bellows tube is not prevented from being pulled out, so that the bellows tube can be pulled out from the main body, so that the connection can be surely confirmed.
The compression state of the spring is released by the insertion of the bellows tube, and the spring expands and is locked to the tube by a retainer that prevents the tube from falling off. Therefore, the function of reliably preventing the tube from falling off is achieved, and at the same time, the sealing with the tube and the stopper can be achieved. In addition, by attaching a lip packing with a U-shaped cross section and inserting the guide pushed by the extension of the spring into the annular recess of the lip packing, the inner and outer surfaces of the packing are expanded, so that reliable sealing performance is obtained. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention before pipe connection.

FIG. 2 is a partial cross-sectional view showing a state during insertion of a pipe according to the first embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing a state after pipe connection according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing a guide 20 according to the first embodiment of the present invention.

FIG. 5 is a perspective view showing a spacer 32 of the present invention.

FIG. 6 is a perspective view showing a retainer 35 according to the first embodiment of the present invention.

FIG. 7 is a longitudinal sectional view showing a second embodiment of the present invention before a bellows tube is connected.

FIG. 8 is a partial cross-sectional view showing a state after the bellows tube connection according to the second embodiment of the present invention.

FIG. 9 is a perspective view of a guide 27 according to a second embodiment of the present invention.

FIG. 10 is a perspective view showing a locking member 55 showing a second embodiment of the present invention.

FIG. 11 is a cross-sectional view of a joint explaining a conventional technique.

[Explanation of symbols]

10 Body 11, 12
Joint main body 13 Step portion 14 Insertion opening 15 Locking groove of main body 16 Locking step portion 20, 27 Guide 21 Locking piece 22 Annular portion 23 Locking convex portion with main body 24 Contact portion with pipe 26 Guide 27 Annular contact part 30 Coil spring 32 Spacer 35 Retainer 36 Tip locking part 37 Annular concave part 38 Cut groove 40 Bellows tube 41 Packing 45 Lip packing 46 Inner peripheral part of packing 45 47 Annular concave part of packing 45 48 Outer peripheral part of packing 45 50 Permselective member 51 Through hole 55 Locking member

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Atsushi Okubo 25-3 Morinodai, Midori-ku, Yokohama, Kanagawa Prefecture (72) Inventor Tomoyuki Minami 5-26-9, Kamikitazawa, Setagaya-ku, Tokyo (72) Inventor Yasushi Fujinawa Saitama 13-14-102, Araimachi, Kawaguchi-shi F term (reference) 3H017 CA03 3J106 AB01 AB09 BB01 BC04 BD01 BE13 BE29 EA03 EB02 EB05 EC01 EC07 ED03 ED14 ED18 EE13 EF04 EF07 EF09 EF09

Claims (12)

[Claims] 1. A plug-in type pipe joint, wherein a low-hardness rubber packing is used for sealing a pipe inserted into the joint body by mounting packing in the joint body. 2. A plug-in type pipe joint, wherein a low-hardness rubber packing is mounted in a joint body, and a bellows pipe having an outer peripheral surface having a corrugated uneven portion is sealed. 3. A plug-in type pipe joint characterized in that a low hardness rubber packing mounted in a joint body is compressed by a spring mounted in the joint body to seal a connecting bellows pipe inserted in the joint body. 4. A spring resilient at an entrance in the axial direction of the main body mounted in the joint main body, a spring locked in the joint main body to hold the spring in a compressed state, and a connecting bellows tube inserted into the joint main body. A guide from which the engagement with the joint body is released at the end of the bellows tube, and a packing which is released from the lock of the guide and is compressed on the outer peripheral surface of the bellows tube by expanding a compressed spring. It is a retaining member which is pushed through the packing by the extension of the spring and is engaged with the corrugated crests of the bellows tube. The stopper is inserted into the joint body to seal and prevent the bellows tube from coming off. A plug-in type pipe joint characterized by the above-mentioned. 5. The packing is a low-hardness rubber packing having a hardness of 25 degrees or less in accordance with JIS Japanese Industrial Standard A hardness. The packing is compressed between a connecting pipe inserted into a joint body, fits into a pipe outer peripheral surface, and is sealed. The plug-in type pipe joint according to any one of claims 1 to 4, wherein 6. The guide has an annular flange portion that receives one end of a spring and presses the packing on the back surface, and a locking portion that extends from the annular flange portion to a depth in the axial direction of the main body and locks with the joint main body. The engaging portion is engaged with a concave groove provided in the joint main body to hold the spring in a compressed state, and the insertion of the bellows tube pushes the engaging portion of the guide, whereby the concave portion is pressed. 6. The lock according to claim 4, wherein the lock is released from the engagement with the groove.
The plug-in type pipe joint described. 7. The bellows tube, wherein the stopper member has an annular locking portion having one end locked in the joint body and an axial split groove at the other end. And the outer peripheral surface of the pivot portion is pushed via the packing by the extension of the spring, the pivot portion is reduced in diameter, and is locked with the bellows tube. The plug-in type pipe joint according to claim 4. 8. The retaining member is an expandable / contractible annular coil ring having a metal coil formed in an annular shape, one end of which is locked in a joint body, and the spring is expanded to allow the annular coil ring and the packing to move. The plug-in type pipe joint according to any one of claims 4 to 6, wherein the annular coil ring is reduced in diameter via a spacer that presses the outer peripheral surface of the annular coil ring mounted therebetween, and is locked to the corrugated uneven portion of the bellows tube. . 9. The retaining member is an expandable / contractible C-shaped ring having a notch in an annular part, one end of which is locked in a joint main body, and the C-shaped ring is extended by expansion of the spring. The C-shaped ring is reduced in diameter via a spacer that presses the outer peripheral surface of the C-shaped ring mounted between the gasket and the packing, so that the C-shaped ring is locked to the corrugated ridges of the bellows tube. The plug-in type pipe joint described. 10. The packing is a U-shaped packing having an annular concave groove in the axial direction, and the guide enters the concave groove of the packing on the back surface of the annular flange to expand the concave groove. 10. The plug-in type pipe joint according to claim 4, further comprising an annular entry portion, wherein the extension of the spring causes the entry portion of the guide to push and expand the concave groove of the packing to seal with the bellows tube. 11. The plug-in type pipe joint according to claim 1, wherein a refractory expansion packing which expands in volume by heat is mounted in the joint body. 12. A watertight packing for sealing with a resin coating layer on an outer peripheral surface of a bellows pipe is attached to an end portion in the joint body,
12. A selectively permeable member, which transmits gas from the inside to the outside but does not transmit solids and liquids, is mounted between the watertight packing and the packing mounting portion.
The plug-in type pipe joint described.