JP2012002255A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint enabling one-touch connection of pipes such as resin pipes to be promptly and easily performed, which can be precisely connected while securing sealing performance by correcting an insertion direction and the position of an axis core in the pipe, and which prevents breakage after pipe connection and improves force preventing pulling-out of the pipe while preventing a total size from being enlarged.SOLUTION: The pipe joint includes a seal member 16 in an outer periphery of an inner cylinder 11 provided in a joint body 2, and has a pipe insertion gap 21 between a resin-made outer cylinder 3, which is provided in the joint body 2 and can be seen through, and the inner cylinder 11. Then, a cap body 4 having a connection mouth 18 at an outer edge side is fixed in the outer cylinder 3 in a state where a pulling-prevention ring 5 is stored. In the pipe joint, a swelling thick section 24 is formed at a side near an outer edge shoulder section of the cap body 4, and the pipe joint has an earthenware-mortar-formed tapered face 26 toward the connection mouth 18 from the swelling thick section 24.

Description

  The present invention relates to a pipe joint capable of connecting a pipe such as a cross-linked polyethylene pipe or a polybutene pipe to, for example, a pipe for water supply / hot water supply for residential facilities or cold / hot water for air conditioning for building facilities.

  Conventionally, a pipe joint called a one-touch joint for resin pipes is known as a pipe joint for connecting resin pipes such as polyethylene pipes and polybutene pipes. This type of pipe joint is capable of connecting pipes quickly and easily while ensuring hermeticity and pull-out resistance, and has a substantially ring-shaped holder for holding the pipe. Is normally stored in a storage space provided between the joint body and the outer cylinder connected to the joint body. In this case, the outer cylinder is formed of metal, a resin cylinder is mounted between the outer cylinder and the joint body, and a holder is disposed between the resin cylinder and the outer cylinder. When the outer cylinder is made of metal as described above, a sealing O-ring is mounted on the inner peripheral side of the resin cylinder, and the outer peripheral surface of the pipe is sealed by the O-ring to form a so-called outer peripheral seal type pipe joint. There are many. Outer seal type pipe joints need to be manufactured taking into account the sealing performance between the outer cylinder and the resin cylinder, and when connecting pipes with scratches on the outer circumference, the sealing performance after connection is poor. There is a demerit that it is easy to get worse.

  Thus, in recent years, resinization of outer cylinders and the like has been promoted. For example, as shown in Patent Documents 1 and 2, a resin outer cylinder is provided on the joint body, and a resin cap member is fixed to the outer cylinder. In many cases, this pipe joint is a so-called inner seal type pipe joint in which an O-ring is mounted on the outer peripheral side of the joint body and the inner peripheral surface of the pipe is sealed by the O-ring. The inner seal type pipe joint has a structure in which the joint body and the pipe are sealed, so there is no need to consider the sealing performance between the outer cylinder and the joint body, which increases the range of material selection for the outer cylinder. It is also possible to use a transparent resin as a material. Since this pipe joint seals the inner peripheral side of the pipe, it can exhibit high sealing performance after being connected to the pipe without being affected by scratches or the like on the outer peripheral side of the pipe. In the inner circumference seal type pipe joint, the cap member is formed of a material different from that of the outer cylinder, and the cap member is connected to the outer cylinder so that the lock ring is accommodated between the outer cylinder. ing.

Japanese Patent No. 3843288 JP 2009-133448 A

  The above-described pipe joint is often constructed in a narrow place such as under the floor or attic in a house, and is often connected in a situation where it is difficult to visually check the connection location. At that time, the pipe may be connected by searching for the insertion port of the pipe. However, in Patent Document 1, a protruding portion is formed at the insertion position of the pipe of the cap member. It becomes difficult to connect the pipe in the correct insertion direction inside. On the other hand, in Patent Document 2, since the end face side of the cap member is flat, it is difficult to understand the position of the hole for connection, and connection by groping becomes difficult. As a result, in these pipe joints, the pipe is inserted in an oblique state to press the lock ring in an oblique direction, the insertion load becomes extremely large, or the O-ring is bitten, resulting in poor connection, Sometimes it was not connected correctly.

  In addition, when a pulling load is applied to the pipe after the pipe is connected, the pulling load is applied to the contact surface of the cap member through the lock ring. In this case, stress concentration acts on the contact surface, and the cap member is easily damaged. In order to avoid this, these pipe joints have a groove-shaped notch near the corner of the abutment surface, and a rounded portion is formed at the corner of this notch, thereby concentrating stress. I try to improve the pull-out prevention power. However, in these cases, when a pulling load is applied, the entire contact surface of the lock ring is deformed so that it bends in the pulling direction with the above-described notched portion or rounded portion as a fulcrum, and the contact surface portion of the cap is damaged. In some cases, sufficient pulling strength cannot be obtained. Also, as in the case of the pipe joint of the same document 1, when a part of the wall near the pipe insertion opening of the cap is formed thicker, or the thickness of the entire cap end is increased to improve the pull-out prevention force In some cases, the balance of stress acting on the cap member when a load is applied to the contact surface is lost, and parts other than the contact surface of the cap may be damaged.

  By the way, the connection between the cap member and the outer cylinder may be based on a snap fit fitting and a screw connection. Further, the snap fit fitting is based on one uneven fitting portion and two or more uneven fittings. There is a thing by the joint part. In the case of forming the above-described notch portion or rounded portion, it is limited to the connection by one uneven fitting portion having a relatively simple shape or the screw connection, and two or more uneven fitting portions are formed. In the case of snap-fit joining, it is difficult to injection-mold the notched portion and the rounded portion, and it has been difficult to improve the pull-out preventing force.

  The present invention has been developed to solve the above-mentioned problems, and the object of the present invention is a pipe joint that can quickly and easily connect a pipe such as a resin pipe, and the insertion direction and axis of the pipe. To provide a pipe joint that can be accurately connected while correcting the position of the heart and ensuring a sealing property, and that can prevent damage after the pipe is connected while improving the overall pull-out prevention force while preventing an increase in the overall size. It is in.

  In order to achieve the above object, the invention according to claim 1 is provided with a sealing member on the outer periphery of the inner cylinder provided in the joint body, and between the see-through resin outer cylinder provided in the joint body and the inner cylinder. A pipe joint that has a pipe insertion gap and a cap body that has a connection port on the outer end side in the outer cylinder, and is fixed in a state in which the retaining ring is housed, and bulges to the vicinity of the outer end shoulder portion of the cap body A pipe joint in which a thick part is formed and a mortar-shaped tapered surface is provided from the bulging thick part toward the connection port.

  In the invention according to claim 2, the bulging thickened portion in the vicinity of the outer end shoulder portion bulges on the outer end side in the axial direction of the inner peripheral round surface of the cap ring against the retaining ring. This is a pipe joint.

  The invention according to claim 3 is the pipe joint in which the outer end portion of the bulging thick portion and the outer end portion of the inner cylinder are substantially flush.

  The invention according to claim 4 is a pipe joint in which an outer cylinder and the cap body are fixed by joining by a multi-stage snap fit.

According to the first aspect of the present invention, it is a pipe joint that can quickly and easily connect a pipe such as a resin pipe, and can seal the inner peripheral side of the pipe with an O-ring to exhibit high sealing performance, and is difficult to see. Even under circumstances, the mortar-shaped taper surface can guide the pipe to the inner cylinder, so the insertion direction of the pipe and the position of the shaft center are corrected to prevent an increase in insertion load and turning of the O-ring to ensure sealing performance. While connecting accurately. Moreover, since the exposure of the inner cylinder can be increased by the tapered surface, it is easy to insert the pipe into the connection port.
On the other hand, when a pulling load is applied to the pipe after the pipe is connected, the cap body can be prevented from being deformed by the bulging wall thickness portion, and the pulling prevention force can be improved while preventing the cap from being damaged.

  According to the second aspect of the present invention, when a pulling load is applied to the pipe, the load can be applied to the bulging wall thickness portion with the inner peripheral round surface as a center, and the concentration of stress is reduced to reduce the concentration of the cap body. Deformation and breakage can be prevented.

  According to the third aspect of the present invention, when the pipe is connected, the tip of the pipe can be brought into contact with the tapered surface so that the tip of the pipe can naturally come into contact with the inner cylinder. It is possible to connect accurately while ensuring the sealing performance in a straight state while matching the direction and the position of the shaft center.

  According to the invention according to claim 4, it is possible to reduce the circumferential thickness of the cap by joining with a multi-stage snap fit, and to reduce the size of the entire pipe joint and use it in a narrow place. In addition, the cap body and the outer cylinder can be firmly connected, and even when a pulling load is applied to the pipe, the cap body can be prevented from being detached from the outer cylinder.

1 is a half-sectional view showing an embodiment of a pipe joint according to the present invention. It is a perspective view of the pipe joint of FIG. It is a principal part expanded sectional view of FIG. It is a principal part expanded sectional view which shows the state which inserted the pipe into the pipe joint. It is the partially expanded sectional view which showed the connection process of the pipe.

  Below, one embodiment of a pipe joint in the present invention is described in detail based on a drawing. 1 and 2 show a pipe joint according to the present invention, and FIG. 3 shows an enlarged cross-sectional view of the main part of FIG. The pipe joint main body 1 in the present invention is used for connection of a pipe 7 for water supply / hot water supply, and has a joint main body 2, an outer cylinder 3, and a cap body 4, and the outer cylinder 3 is connected to the joint main body 2. The outer cylinder 3 and the cap body 4 are fixed in a state where the retaining ring 5 is housed. An insertion guide 6 is mounted on the joint body 2.

  The joint body 2 is formed in a substantially cylindrical shape from a metal such as a copper alloy or a highly synthetic resin such as PPS (polyphenylene sulfide), and the joint body 2 has a water passage for flowing water. The part 10, the inner cylinder 11, the fitting mounting part 12, the nut part 13, and the connection part 14 are provided. A mounting groove 15 is formed on the outer periphery of the inner cylinder 11 of the joint body 2, and the mounting groove 15 is provided with a seal member 16 made of an O-ring. The pipe 7 can be connected to the outer periphery of the inner cylinder 11, and the pipe joint body 1 has a structure of an inner peripheral seal type one-touch joint in which the inner periphery of the pipe 7 is sealed and connected by a seal member 16. The fitting / mounting portion 12 is formed in a concavo-convex shape on the outer peripheral side of the inner cylinder 11 and is provided so as to be able to be joined to a fitting / mounting portion 17 of the outer cylinder 3 described later by snap-fit fitting. The nut portion 13 is provided adjacent to the fitting mounting portion 12, and the joint body 2 can be rotated relative to the outer cylinder 3 by gripping and rotating the nut portion 13. Yes. The connection portion 14 is formed in the form of a male screw portion, and an external pipe (not shown) or the like can be connected to the connection portion 14.

  The insertion guide 6 inserted into the joint body 2 is made of, for example, elastic high-density polyethylene, and slits (not shown) are alternately formed on the front and rear end sides. The insertion guide 6 is mounted on the outer peripheral side of the inner cylinder 11 so that the pipe 7 can be smoothly guided. Moreover, even when the tip of the pipe 7 is cut obliquely, the insertion guide 6 is deformed following the shape of the tip of the pipe 7 by the slit, so that the pipe 7 is reliably guided.

  The outer cylinder 3 is made of a resin that can be seen through, and a concave and convex fitting mounting portion 17 is formed on the connection side of the outer cylinder 3 with the joint body 2 on the inner circumference side, while the cap body on the outer circumference side is formed. A plurality of, for example, two-stage uneven fitting portions 20 are formed on the connection side with the four. In the outer cylinder 3, the fitting mounting portion 17 is joined to the fitting mounting portion 12 by snap fitting and fixed to the joint body 2, and a pipe insertion gap 21 is provided between the outer cylinder 3 and the inner cylinder 11 of the joint body 1. Is formed. The pipe 7 is connected to the insertion gap 21 while being guided by the outer cylinder 3, and this outer cylinder 3 is preferably formed of a resin such as amorphous nylon or PPSU (polyphenylsulfone). In this case, it is possible to visually check the state of the pipe 7 and the insertion guide 6 from the outside of the outer cylinder 3.

  The cap body 4 is provided to fix the retaining ring 5 in a state where it is housed in a predetermined position in the pipe joint body 1, and has a higher tensile elastic modulus than the outer cylinder 3, for example, a resin such as POM (polyacetal). It is formed by. A connection port 18 for pipe connection is formed on the outer end side of the cap body 4, and a contact surface 27 with which the retaining ring 5 can abut is formed on the opposite side of the connection port 18. An inner peripheral round surface 30 is formed on the outer diameter side. It is preferable that the inner circumferential radius surface be a radius of about 0.4 mm, for example, when the distance L described later is 3 mm and the distance M is 1 mm.

  A bulging thickened portion 24 is formed near the outer end shoulder portion of the cap body 4, and the bulging thickened portion 24 bulges toward the axially outer end side of the inner peripheral round surface 30 of the cap body 4. Is formed. Furthermore, a mortar-shaped tapered surface 26 is provided at a predetermined angle from the bulging thick portion 24 toward the connection port 18. On the inner peripheral side of the cap body 4, a plurality of concavo-convex fitting portions 22 that can be fitted to the concavo-convex fitting portion 20, for example, two tiers are formed. The cap body 4 and the outer cylinder 3 are fixed to each other by joining of the plurality of concavo-convex fitting portions 20 and 22 by snap fitting.

  In FIG. 4, the distance L in the cap body 4 represents the axial length from the contact surface 27 to the inner peripheral end 28 of the tapered surface 26, that is, the minimum thickness of the pipe insertion side portion 4 a of the cap body 4. The distance M indicates the axial length from the inner peripheral end 28 to the outer end portion 29 of the bulging thick portion 24, that is, the maximum thickness of the bulging thick portion 24. The ratio between the distance L and the distance M is preferably, for example, distance L: distance M = 3: 1 to 2: 1, and particularly preferably 3: 1. In this case, when the distance L is 3 mm, the distance M is 1 mm, that is, when the axial thickness (distance L) is 3 mm, the taper surface 26 has an axial depth of 1 mm. Furthermore, the distance L in the present embodiment is set to be approximately equal to the thickness W of the concave / convex fitting portion side portion 4b of the cap body 4.

If the ratio of the distance L to the distance M is less than 3: 1, the strength of the pipe insertion side portion 4a of the cap body 4 becomes too weak, and when a pulling load is applied to the pipe 7, the pipe insertion side portion 4a May tilt around the inner radius surface 30 of the contact surface 27 as a fulcrum.
On the other hand, when the ratio of the distance to the distance M exceeds 2: 1, the strength of the pipe insertion side portion 4a of the cap body 4 becomes too strong, and when the pulling load is applied to the pipe 7, the uneven fitting portion 20 is It may be damaged or the fitting with the outer cylinder 3 may be released.

  As a comparative example, assuming that the thickness of the pipe insertion side portion 4a of the cap body 4 is all set to the distance M + distance L without providing the taper surface 26, the shape is close to the prior art, and the pipe insertion side The strength of the portion 4a becomes too strong. Moreover, it becomes difficult to insert the pipe 7.

The starting point P on the outer end side of the tapered surface 26 is the diameter of the outer diameter side starting point 30a of the inner peripheral round surface 30 (in this embodiment, the diameter on the valley side of the concave-convex fitting portion 22 in the axial direction of the cap body 4). And substantially the same diameter). By forming the tapered surface 26 based on the starting point P, a balance is achieved between the strength improvement in the vicinity of the contact surface 27 by the bulging thick portion 24 and the prevention of breakage of the cap body 4 and the connection portion with the outer cylinder 3. However, the tapered surface 26 is formed to be large in the radial direction, so that the pipe 7 can be smoothly corrected to the correct mounting state. Although not shown, the starting point of the taper surface 26 is provided to be substantially the same diameter as the diameter of the inner diameter side starting point 30b of the inner peripheral round surface 30 (in this embodiment, the diameter on the mountain side of the concave-convex fitting portion 22). Alternatively, it is possible to cut out the cap at the corresponding position in a stepped shape, thereby providing a bulging thick portion.
In the figure, a tapered surface portion is formed on the outer diameter side of the outer end side of the cap body 4 with respect to the tapered surface 26, but this tapered surface portion is formed in an appropriate shape or omitted. You can also.

  One retaining ring 5 shown in FIG. 3 is accommodated between the contact surface 27 and the end surface 25 of the outer cylinder, and this retaining ring 5 is formed in a substantially annular shape from stainless steel or the like. On the inner diameter side of the retaining ring 5, a holding claw 31 is bent at a predetermined inclination angle. The retaining ring 5 is housed in a state where a gap G is provided between the outer cylinder 3 and the cap body 4, and the holding claw 31 is disposed at a position facing one seal member 16. The pipe 7 can be prevented from coming off by being locked to the surface of the pipe 7.

As described above, the joint body 2, the outer cylinder 3, and the cap body 4 are fixed together by the snap fitting of the fitting mounting portions 12 and 17 and the concave and convex fitting portions 20 and 22, and each of them can be rotated. Yes. At that time, the cap body 4 and the outer cylinder 3 are joined by the snap fitting of the concave and convex fitting portions 20 and 22 rather than the strength of the contact surface 27 required when a pulling load is applied to the connected pipe 7. It is formed so that the strength is equal to or higher.
And after these integration, the outer end part 29 of the bulging thick part 24 and the outer end part 32 of the inner cylinder 11 will be in a substantially flush state in the axial direction.

  Further, the cap body 4 is formed in advance so that the extension line of the tapered surface 26 faces the outer peripheral plane portion of the inner cylinder 11 after being assembled. As a result, the pipe 7 comes into contact with the tapered surface 26, and when the pipe end portion 33 is guided along the tapered surface 26, the pipe end portion 33 is reliably guided to the inner cylinder 11. In this case, if the taper angle α is small, the pipe 7 is guided to the rounded surface portion 34 at the tip of the inner cylinder shown in FIG. On the other hand, when the taper angle α is large, the pipe 7 comes into contact with the internal parts such as the retaining ring 5 at an inappropriate angle, and the internal parts and the pipe 7 may be damaged. It is necessary to set the taper angle α in consideration of these matters.

  In FIG. 3, the length C between the inner end surface 35 of the cap body 4 and the inner cylinder outer peripheral surface 36 is set to be slightly larger than the thickness T of the pipe 7 in FIG. 4. By suppressing the length C as small as possible in this way, the outer peripheral surface side of the pipe 7 comes into contact with the inner end surface 35 when the pipe is connected, and the axis Q of the pipe 7 is the axis R of the pipe joint body 1. Therefore, it is possible to suppress the holding claw 31 of the lock ring so as to protrude slightly from the inner end surface 35 to the inner peripheral side. Accordingly, it is not necessary to form the retaining ring 5 larger than necessary, and the retaining ring 5 and other internal parts can be downsized.

  As the pipe 7 shown in FIG. 4, for example, resin pipes made of various materials such as cross-linked polyethylene pipes and polybutene pipes can be used, or metal reinforced resin pipes such as metal reinforced polyethylene pipes can be used. Is also possible.

Then, the case where a pipe is connected to the pipe joint main body in embodiment mentioned above is demonstrated.
FIG. 5A shows a case where the pipe 7 is connected to the pipe joint body 1 in a shifted state, and shows a state in which the pipe end 33 is in contact with the tapered surface 26.

  When the pipe 7 is inserted from this state, the pipe 7 is guided toward the inner cylinder 11 along the mortar-shaped tapered surface 26 as shown in FIG. At this time, the outer end portion 29 of the bulging thick portion 24 and the outer end portion 32 of the inner cylinder 11 are provided substantially flush with each other, so that the pipe end portion 33 is immediately in contact with the tapered surface 26. It is possible to quickly find the pipe insertion gap 21 by naturally contacting the cylinder 11. In addition, since the tapered surface 26 is formed on the cap body 4, the exposed portion on the outer peripheral surface side of the inner cylinder 11 becomes larger, and the insertion gap 21 can be more easily searched than when the cap tip side is flat. .

Next, in FIG. 5C, when the pipe 7 is further inserted, a part of the pipe end portion 33 is in contact with the inner cylinder 11, so that the entire pipe end portion 33 is a tapered surface with this contact portion as a fulcrum. As a result, the pipe 7 is corrected from an obliquely inserted state to a state substantially parallel to the pipe joint body 1, and with respect to the axis R of the pipe joint body 1. Thus, the shaft Q is straightly inserted into the insertion gap 21 in a state of alignment.
5A, the pipe 7 is inserted in an inclined state or in a state where the axis R of the pipe joint main body 1 and the axis Q of the pipe 7 do not coincide with each other. Even in this case, the pipe 7 is guided to the insertion gap 21 while being corrected to the correct mounting state by the taper surface 26 and connected to the pipe joint body 1.

  If the pipe 7 is inserted to a predetermined position after the pipe 7 in FIG. 5C is corrected, the retaining claws 31 of the retaining ring 5 bite into the outer peripheral surface of the pipe 7 and are prevented from coming off. The inner peripheral surface side of the pipe 7 is surely hermetically sealed by the seal member 16.

  When a pulling load is applied to the pipe 7 after connecting the pipe 7 to the pipe joint body 1, the retaining ring 5 moves in the direction of the tip of the cap body 4 together with the pipe 7 and comes into contact with the contact surface 27. When a larger pulling load is applied to the pipe 7 from this state, a force is exerted on the cap body 4 to deform in the counterclockwise rotation direction in FIG. 4 about the inner peripheral radius surface 30 of the contact surface 27. Since the bulging thick part 24 bulges on the outer end surface in the axial direction of the shaft 30, the bulging thick part 24 can particularly improve the strength of a portion where a large load is applied. Deformation can be prevented.

  In addition, since the outer cylinder 3 and the cap body 4 are joined by snap fitting with the plurality of steps of the uneven fitting portions 20 and 22, the plurality of steps of protrusions and recesses are made while reducing the thickness of the cap body 4 in the radial direction. The connection portions between the cap body 4 and the outer cylinder 3 can be firmly connected by the fitting portions 20 and 22 to prevent damage in the vicinity thereof.

  As described above, by providing the bulging thick portion 24, the strength in the vicinity of the contact surface 27 is improved, and the connection strength between the cap body 4 and the outer cylinder 3 is improved by the plurality of uneven fitting portions 20, 22. Therefore, it is possible to maintain the stress balance acting on both sides when the drawing load is generated, to prevent the cap body 4 from being damaged, and to improve the pulling-in preventing force of the pipe 7. Moreover, by providing the bulging wall thickness portion 24, the pipe insertion side portion 4a wall thickness (distance L) of the cap body 4 is provided to the same extent as the wall thickness of the concave / convex fitting portion side portion 4b of the cap body 4, The strength in the vicinity of the contact surface 27 can be improved while providing the entire cap body 4 in a small size.

  As described above, the pipe joint according to the present invention has a bulging wall thickness portion 24 formed near the outer end shoulder portion of the cap body 4 and a mortar shape from the bulging wall thickness portion 24 toward the connection port 18. The formed taper surface 26 can be connected while correcting the insertion direction and the position of the shaft center when the pipe 7 is inserted, and the cap body 4, the cap body 4, and the outer cylinder when a pulling load is applied to the pipe 7. The function of preventing breakage of the connection part 3 can be exhibited synergistically.

DESCRIPTION OF SYMBOLS 1 Pipe joint main body 2 Joint main body 3 Outer cylinder 4 Cap body 5 Retaining ring 11 Inner cylinder 16 Seal member 18 Connection port 20,22 Concavity and convexity fitting part 21 Pipe insertion gap 24 Swelling thick part 26 Tapered surface 27 Contact surface 29 , 32 Outer end 30 Inner peripheral round surface

Claims (4)

  A seal member is provided on the outer periphery of the inner cylinder provided in the joint main body, and a pipe insertion gap is provided between the inner cylinder and the see-through resin outer cylinder provided in the joint main body. A pipe joint fixed with a cap ring having a connection port on the side in a state in which a retaining ring is housed, and a bulging wall thickness portion is formed near the outer end shoulder portion of the cap body. A pipe joint comprising a mortar-shaped tapered surface from a portion toward the connection port.   2. The bulging thickened portion in the vicinity of the outer end shoulder portion is a portion bulging and formed on the outer end side in the axial direction of the inner peripheral round surface of the cap body on the contact surface of the retaining ring. The described pipe joint.   The pipe joint according to claim 1 or 2, wherein an outer end portion of the bulging thick portion and an outer end portion of the inner cylinder are substantially flush with each other.   The pipe joint according to any one of claims 1 to 3, wherein the outer cylinder and the cap body are fixed by joining with a plurality of stages of snap fits.

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