JPH1089561A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint which can improve a sealing property of a sealing material interposed between a receiving port and an inserting port by a simple structure and more surely prevent the slipping-off of the pipe without deteriorating workability. SOLUTION: A lip 4b of a packing 4 is made on the outer peripheral surface of a cylindrical part 4a and the cylindrical part 4a is enlarged in diameter and fitted on an inserting port 3a and this assembly is inserted into a receiving port 2. Since the cylindrical part 4a can be fitted on the inserting port 3a with sufficient elastic deformation, the elastic restoring force of the cylindrical part 4a having a large contact area with the inserting port 3a can produce a stable water-sealing property by a simpler constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pipe joint used for connecting pipes such as a drain pipe.

[0002]

2. Description of the Related Art When connecting drain pipes in a high-rise building or the like, pipes are connected at appropriate locations. Examples of pipe joints used for connecting such pipes are disclosed in, for example, JP-A-1-269787.
No., published in Japanese Unexamined Patent Publication No. In the pipe joint, a rubber packing (seal member) 40 having a shape shown in FIG. 8 is used.
The packing 40 is formed by providing a tongue-like inwardly protruding lip (inner seal) 42 on the inner surface of a substantially cylindrical main body 41. In addition, on the outer peripheral surface of the main body portion 41,
A small tongue-shaped piece 43 protruding outward and a ridge 44 protruding in a triangular cross section are further provided.

As shown in FIG. 9, the packing 40 is fitted in advance along an inner surface of a receiving port 45 provided at a pipe end of one of the pipes. In this fitted state, the tongue-shaped piece 43 elastically deformed along the inner surface of the receiving port 45 provides a sealing property between the outer peripheral surface of the main body 41 and the inner peripheral surface of the receiving port 45. In addition,
The protruding portion 44 is fitted into a concave groove formed on the inner surface of the receiving port 45 and is engaged in the axial direction, thereby preventing the packing 40 from coming off from the receiving port 45.

[0004] By inserting a tube end side of the other tube (hereinafter, referred to as a connection tube) 46, that is, a so-called spout 47 into the packing 40, the connection tube 46 is connected to the receiving port 45. At this time, the insertion of the spigot 47 causes the lip portion 42 to elastically deform and
It is in close contact with the outer peripheral surface, thereby providing sealing between the packing 40 and the spigot 47. Thus, in the above description, the sealing property between the packing 40 and the spout 47 is given by the elastic recovery force of the packing 40 that is elastically deformed in accordance with the insertion of the spout 47. It also becomes insertion resistance at the time of insertion work. In this case, the close contact with the spigot 47 is only the lip portion 42 that partially protrudes from the inner surface of the main body portion 41, so that the close contact area is relatively small.
The sliding resistance when the packing 40 and the connection pipe 46 relatively move in the axial direction can be suppressed relatively small. As a result, the spigot 47 can be inserted into the packing 40 without requiring excessive force, and the construction can be easily performed. Conventionally, a flange joint structure is mainly used for connecting drainage pipes and the like, but in comparison with this structure, there is no need to provide a flange or the like, and since fastening work with bolts and nuts is not required, The whole is more compact, and the workability can be improved.

[0005]

However, in the pipe joint described in the above-mentioned publication, the tongue-shaped piece for imparting a sealing property between the cylindrical main body portion 41 and the inner surface of the receiving port 45 of the packing 40 is provided.
Reference numeral 43 denotes a configuration in which this is elastically deformed so as to fall into the main body 41, and in this case, the dimensions and the amount of elastic deformation of the tongue-shaped piece 43 are too small in consideration of the thickness and the like of the main body 41. Can't be bigger. For this reason, in consideration of the variation in the pipe diameter and the surface roughness of the pipe, there is a problem that it is difficult to stably obtain the sealing property based on the elastic force, and the range of use is limited.

Further, instead of the tongue piece 43 as described above, it is also conceivable to adopt a structure in which the main body 41 is compressed in the axial direction after the insertion of the tube so as to increase the degree of close contact of the main body 41 with the socket 45. However, in this case, the entire configuration becomes complicated. On the other hand, the above-mentioned pipe joint has a structure in which the ridge portion 44 of the packing 40 is axially engaged with the receiving port 45 to prevent the packing 40 from coming off from the receiving port 45. For the connection tube 46 to come off from
Only the sliding resistance based on the elastic recovery force in 42 functions. As described above, since the sliding resistance is set in consideration of the insertion force at the time of the insertion work of the spigot 47, for example, if the water pressure flowing through the inside becomes high, the internal pressure becomes large.
Since the connection pipe 46 acts as a force in the removal direction from the receiving port 45 against the connection pipe 46, there is a possibility that the connection pipe 46 will be removed, and thus the range of use is also limited.

[0007] In order to ensure that such a tube is prevented from coming off even in the case of a greater force in the direction of coming off, for example, an engagement groove is provided on the outer peripheral surface of the spigot 47, and this engagement is provided. The member fitted into the mating groove is further locked to the socket 45, and the spigot
It is conceivable to adopt a configuration in which the 47 and the receiving port 45 are engaged in the axial direction. However, in general, the connecting pipe 46 is often used by appropriately cutting the spigot 47 in order to adjust the length at the site. The structure requires additional work on site, and the workability is greatly reduced.

The present invention has been made in view of the above-mentioned conventional problems, and it is possible to improve the sealing performance of a sealing member interposed between a receiving port and a port with a simple structure. In addition, it is another object of the present invention to provide a pipe joint that can more reliably prevent the pipe from coming off without lowering the workability.

[0009]

In order to achieve the above-mentioned object, a pipe joint according to a first aspect of the present invention comprises an inner peripheral surface of a receiving port of a first pipe and a second pipe inserted into the receiving port. A pipe joint in which a seal member made of an elastic body is interposed between the outer peripheral surface of the spout and a substantially cylindrical main body part whose diameter is enlarged and fitted to the spout. It is characterized in that it is formed in a shape having an outer seal portion which projects radially from the outer peripheral surface of a part of the main body in the axial direction and is pressed against the inner peripheral surface of the receiving port.

[0010] In the sealing member having the above-described structure, before the spigot is inserted into the socket, the substantially cylindrical main body is expanded in diameter and attached to the spigot, and the spigot is inserted into the socket. The elastic recovery force accompanying the deformation of the outer seal portion at the time of insertion gives a seal between the seal member and the inner peripheral surface of the receiving port. this is,
As before, it also acts as insertion resistance during the above-mentioned insertion work, but since the area of close contact of the outer seal portion with the inner surface of the receiving port is appropriately small, excessive sliding resistance does not occur, and therefore, insertion is easy. It can be carried out.

On the other hand, the sealing property between the sealing member and the outer peripheral surface of the spout is given by the elastic recovery force of the main body. That is, the main body is configured to be fitted externally to the spigot, and in this case, the main body can be mounted with a desired amount of elastic deformation in the diameter increasing direction. In addition, the main body has a large contact area with the outer surface of the spigot. As a result, as in the above-described conventional example, a tongue-shaped piece is further provided on the contact surface of the main body, or the main body is compressed in the axial direction. Without a complicated structure such as separately providing a pressing member, a more reliable sealing property can be stably obtained with a simple structure.

According to a second aspect of the present invention, in order to prevent the seal member from being pulled out from the inside of the socket, the pipe joint is further provided with retaining means for engaging the socket and the seal member in the axial direction. And That is, for the sealing member and the spigot, for example, by the elastic recovery force of the main body described above,
Sliding resistance that prevents these axial relative movements can be generated. Therefore, as described above, the retaining member for engaging the seal member with the receiving port in the axial direction is provided, and by preventing the removal of the sealing member from the receiving port, the second tube can be removed from the receiving port. Can be prevented. In this case, it is not necessary to apply any special processing to the spout, so that the structure for preventing the pipe from coming off can be made simpler, and the structure does not require any additional work on site. Therefore, good workability can be maintained.

According to a third aspect of the present invention, the outer seal portion is provided on the inner side of the main body portion in the axial direction, and the retaining means is provided between the outer seal portion and the main body portion which is closer to the opening end than the outer seal portion. It is characterized by comprising a ring body having a steadying portion inserted into a space between the inner peripheral surface of the mouth. That is, in the interposed state of the seal member, a space is formed between the outer peripheral portion and the inner peripheral surface of the receiving port in a region excluding the outer seal portion.
The concentricity between the spigot and the socket is maintained by the elastic force of the outer seal portion interposed in a part of the axial direction. In this case, if an eccentric external force acts on the second pipe, pipe runout is likely to occur only with the elastic force of the outer seal portion.

Therefore, in the above description, the outer seal portion is provided on the inner side in the axial direction of the main body portion, and the retaining means for preventing the second tube from coming off from the receiving port is constituted by a ring body. A steady rest portion is further provided to fill the space. Accordingly, the tube runout is suppressed without separately providing a dedicated member for preventing the tube runout, and concentricity with the receiving port of the outer seal portion is maintained. Therefore, with a simpler configuration, it is ensured that the press-contact state of the outer seal portion against the inner peripheral surface of the receiving port becomes more uniform over the entire circumference, and as a result, better sealing performance is maintained.

[0015]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a first tube (hereinafter, referred to as a first tube).
In the socket 2 provided at the pipe end of the
A pipe end portion (hereinafter, referred to as a connection pipe) of a second pipe (hereinafter, referred to as a connection pipe) 3
Insert this tube end into the outlet 3a.
3 are coaxially connected to each other. In the case of drain pipes, these pipes 1 and 3 are, for example, JIS standard FCD50
It is formed of a cast iron tube consisting of zero. A packing (seal member) 4 made of an elastic body for providing water stoppage and a retaining ring (for preventing the connection pipe 3 from coming off from the receiving port 2) are provided between the receiving port 2 and the outlet 3a. A retaining means 5 is interposed.

As shown in FIG. 2, the receiving port 2 has a cylindrical wall 2a whose inner and outer diameters are slightly larger than the connecting pipe 3. The opening end side of this cylindrical wall 2a is formed in a substantially F-shaped cross section, and at the position of the opening end, a locking flange 2b is provided which projects perpendicularly to the pipe axis and projects inward from radially outward. I have.
The diameter of the inner peripheral surface of the locking flange 2b is substantially the same as the inner diameter of the cylindrical wall 2a. An engagement groove 2c having a substantially F-shaped cross section that is recessed radially outward from the inner peripheral surface of the cylindrical wall 2a is provided on the inner side (lower side in the figure) of the locking flange 2b in the axial direction. Have been. On the other hand, the lower end of the cylindrical wall 2a is joined to the lower tube portion 2e via a step wall 2d that extends radially inward perpendicular to the tube axis.

The packing 4 is made of, for example, an elastomer such as ethylene propylene rubber, styrene butadiene rubber, or chloroprene rubber. As shown in FIG. 3, the packing 4 has a cylindrical portion (body portion) 4a having a predetermined axial length. A lip portion (outer seal portion) 4b having a shape that is inclined obliquely upward and protrudes outward on the outer periphery of the lower end side in the drawing of the cylindrical portion 4a.
Are provided in an annular shape. The cylindrical portion 4a is formed to have a diameter smaller than the outer diameter of the connection pipe 3, and an inner peripheral surface at a lower end portion of the cylindrical portion 4a has a size corresponding to the thickness of the connection pipe 3 and is radially inward. The projecting tube receiving portion 4c is formed in a step shape.

The retaining ring 5 is made of, for example, a synthetic resin material such as polypropylene or polyethylene, or a metal material having elasticity such as spring steel. As shown in FIG. It is provided and configured. At the four positions in the circumferential direction of the cylindrical main body 6, lower connecting walls 7 which are provided in a circumferential direction over the lower half of the cylindrical main body 6 are provided. On each upper part of the lower connecting walls 7, upper movable walls 8, which are circumferentially separated from each other by a predetermined gap from the cylindrical main body 6, are connected to each other.

Each lower connecting wall 7 is formed in a flat plate shape, and both ends in the circumferential direction are connected to each other so that the inner surface is located slightly radially outward from the inner circumferential surface of the cylindrical main body 6. Is connected to the cylindrical main body 6 through the main body. Each upper movable wall 8
Also, the shape along the circumferential direction is formed as a flat plate except that the outer surface of a claw portion 8d described later is arc-shaped.
Therefore, when an external force in the radial direction acts on these upper movable walls 8, these movable walls 8 can be bent and deformed in the radial direction with the portion connected to the lower connecting wall 7 as a fulcrum.

As shown in FIG. 5, a flange 6a extending radially outward is continuously provided on the upper end surface of the cylindrical main body 6.
On the other hand, as shown in FIG. 6, each upper movable wall 8 has a base inclined wall 8a inclined obliquely upward from the upper end position of the lower connecting wall 7 outward in the radial direction, and an upper end of the base inclined wall 8a. The vertical wall 8b extending upward and the upper end inclined wall 8c which is inclined obliquely upward from the upper end of the vertical wall 8b and protrudes upward from the upper surface of the cylindrical main body 6 are formed in such a form that they are sequentially connected. I have.

A claw portion 8d is formed on a radially outer surface of a continuous portion between the base inclined wall 8a and the vertical wall 8b so as to protrude outward in a stepped manner with respect to the vertical wall 8b. . Next, an operation procedure for connecting pipes using the pipe joint having the above configuration will be described with reference to FIG. In the connection work, first, as shown in FIG.
The retaining ring 5 is fitted to the outside of the tube and held at a position appropriately separated from the end of the tube. Next, the packing 4 is attached to the spigot 3a. This packing 4 has a cylindrical portion 4a as described above.
The inner diameter of the cylindrical portion 4a is smaller than the outer diameter of the spout 3a. Therefore, the cylindrical portion 4a is inserted into the spout 3a while expanding the diameter. This insertion is performed as shown in FIG.
Until it adheres.

In this mounted state, the elastic characteristics of the packing 4 and its shape and dimensions are set so that the cylindrical portion 4a is in close contact with the spigot 3a with a sufficiently large surface pressure. by this,
Water stoppage between the packing 4 and the outlet 3a is provided.
Further, the cylindrical portion 4a having a relatively long axial dimension.
When the packing 4 and the connecting pipe 3 move relative to each other in the axial direction, a large sliding resistance is generated between the packing 3 and the connecting pipe 3 because the mounting state is such that a large surface pressure is generated between the packing 3 and the port 3a. As a result, even if an external force having a magnitude normally supposed to be applied to the connection pipe 3 in the release direction in the pipe connection state described later, the detachment of the connection pipe 3 from the packing 4 can be sufficiently performed by the above-described sliding resistance. It has been blocked.

When it is assumed that the pressure in the pipe is higher and a large force acts on the connecting pipe 3 in the pulling-out direction, the cylindrical part 4a of the packing 4 is attached to the spout 3a with an adhesive. It may be in a mounted state where it is used and adhered. In this case, in addition to the elastic recovery force of the cylindrical portion 4a, the adhesive force of the adhesive acts as a force against the release direction, whereby the packing 4 can be more firmly attached to the spout 3a. .

After the attachment of the packing 4 to the spout 3a is completed as described above, a lubricant such as soapy water is applied to the inner surface of the spout 2 and the surface of the lip portion 4b, and the spout 3a is inserted into the spout 2. insert. The packing 4 is expanded in diameter and attached to the spigot 3a.
The outer diameter of 4a is smaller than the inner diameter of the cylindrical wall 2a in the receiving port 2, and the lip portion 4b projects radially outward from the inner peripheral surface of the cylindrical wall 2a. Therefore, when inserting the spigot 3a into the receptacle 2, the outer distal end side of the lip portion 4b is bent radially inward in accordance with the inner diameter of the cylindrical wall 2a in the receptacle 2. As shown in FIG.
As shown in (c), the spigot 3a is inserted into the spout 2 until the pipe receiving portion 4c of the packing 4 is in close contact with the step wall 2d of the spout 2. In this inserted state, the above-mentioned elastic recovery force of the lip portion 4b imparts water stopping between the inner surface of the receiving port 2 and the packing 4.

After the spigot 3a is inserted into the receptacle 2, the retaining ring 5 held above the port 3a is moved along the connecting pipe 3 and inserted into the receptacle 2. With the operation of inserting the retaining ring 5, first, the lower side of the cylindrical main body 6 and the lower connecting wall 7 enter the space between the cylindrical portion 4 a of the packing 4 and the inner surface of the receiving port 2. During this insertion operation, the base inclined wall 8a of the upper movable wall 8 comes into contact with the inner peripheral edge of the locking flange 2b at the upper end of the receiving port 2, and in the process of continuing the insertion further from this point, the upper movable wall 8 The base inclined wall 8a and the claw 8d above the base inclined wall 8a sequentially pass through the gap between the locking flange 2b and the cylindrical portion 4a of the packing 4 while inwardly deforming.

Then, as shown in FIG.
By pushing the retaining ring 5 to a position where the upper end flange 6a comes into contact with the upper end surface of the receiving port 2, the pipe connection operation is completed. Immediately before this work is completed, the claw portion 8d is positioned below the locking flange 2b. At this time, the pressing force of the locking flange 2b against the upper movable wall 8 inward in the radial direction is reduced. As a result, the upper movable wall 8 elastically returns instantaneously to the state shown in FIG.

When the upper movable wall 8 is elastically restored in this manner, the claw portion 8d is fitted into the engagement groove 2c of the receiving port 2, so that the retaining ring 5 is connected to the claw portion 8d and the locking flange. Withdrawal from the inside of the socket 2 is prevented by the axial engagement with 2b. On the other hand, the lower end of the retaining ring 5 is located above and close to the lip 4b of the packing 4. Therefore, when the connecting pipe 3 moves in the direction of pulling out from the receiving port 2, the packing 4 fixed to the spigot 3 a also moves integrally, and the lip portion 4 b contacts the retaining ring 5 from below. . This prevents further movement, and thus prevents the connection pipe 3 from coming off.

As described above, when the upper movable wall 8 is elastically restored and the claw 8d is fitted into the engagement groove 2c, the outer surface of the vertical wall 8b instantaneously comes into contact with the locking flange 2b from inside. The vertical wall 8b is positioned at the locking flange 2b so that it makes a clicking sound
It is set according to the inner surface dimensions. by this,
The operator can confirm by sound that the above-mentioned assembled state is obtained by inserting the retaining ring 5.

The engaging groove 2c is formed on the inner surface of the receiving port 2 over the entire circumference. Therefore, when inserting the retaining ring 5, since the circumferential angular position with respect to the receptacle 2 is arbitrary and has no directivity, the inserting operation of the retaining ring 5 itself can be performed very easily.
On the other hand, in the above configuration, the connection state can be easily released when the connection pipe 3 is replaced or the like. That is, the upper movable wall 8 of the retaining ring 5 has
An upper end inclined wall 8c projecting upward from the flange 6a is provided integrally. Therefore, by pressing this inward in the radial direction, the claw portion 8d is located inside the inner surface of the locking flange 2b. In this state, the retaining ring 5 can be pulled out from the receiving port 2. Thereafter, by applying a pull-out force against the elastic recovery force of the lip portion 4b of the packing 4, the connection pipe 3 can be pulled out from the receiving port 2 together with the packing 4. The new connecting pipe 3 is replaced with the packing 4 as described above.
Is attached to the outlet 3a, and is connected to the receptacle 2 in the same operation procedure as described above.

As described above, the packing 4 in the present embodiment has the lip portion 4b provided on the outer peripheral surface of the cylindrical portion 4a, and the packing 4 is previously mounted on the spigot 3a of the connection pipe 3. Into the receptacle 2. Due to the elastic recovery force based on the elastic deformation of the lip portion 4b accompanying this insertion, the waterproofness between the packing 4 and the inner surface of the receiving port 2 is given. Also,
The elastic recovery force of the lip portion 4b also serves as insertion resistance during the insertion operation, but since the contact area of the lip portion 4b with the receiving port 2 is relatively small, the insertion operation can be performed with a smaller force.

On the other hand, the waterproofness between the inner surface of the packing 4 and the spout 3a is given by the elastic recovery force of the cylindrical part 4a when the diameter of the cylindrical part 4a is expanded and mounted on the spout 3a. That is,
The packing described in the above-mentioned publication has a configuration in which the cylindrical portion is fitted into the receiving port. In this case, in order to obtain a stable water stoppage by the elastic recovery force of the cylindrical portion, the cylindrical portion is reduced in diameter. It is necessary to elastically deform in the direction to mount. However, even with an elastic body, it is usually impossible to uniformly deform a cylindrical one in the diameter reducing direction, and even if it is press-fitted and assembled, the deformation amount corresponding to the press-fitting margin is small. It's just Therefore, this small amount of deformation cannot cope with variations in tube diameter and the like, and it is difficult to obtain stable water stoppage due to the elastic recovery force of the cylindrical portion.

On the other hand, in the present embodiment, the packing 4
As described above, by providing the lip portion 4b on the outer surface of the cylindrical portion 4a, the lip portion 4b can be attached to the cylindrical portion 4a by giving a desired amount of elastic deformation in the radially expanding direction, and
The cylindrical portion 4a has a larger contact area with the outer surface of the spigot 3a than the lip portion 4b which needs to set the contact area in consideration of the resistance at the time of insertion work, and therefore, the elastic recovery force of the cylindrical portion 4a It is possible to provide stable water stoppage with the outlet 3a.

In particular, since the contact area between the packing 4 and the spigot 3a can be increased as described above, even if the connecting pipe 3 has a rough surface such as the above-described cast iron pipe, It is possible to obtain stable water stoppage. Furthermore, when the joint pipe 1 having the receiving port 2 is a joint part called, for example, a socket or a tee, such small parts are usually subjected to powder coating on the surface, thereby smoothing the surface. It has become something. On the other hand, the connecting pipe 3 on the side of the outlet 3a is generally long, and it is difficult to apply powder coating to such a long cast iron pipe in terms of equipment, and the surface is used with a rough surface. In the case of such a combination of the joint pipe 1 and the connection pipe 3, since the lip portion 4b comes into close contact with the receiving port 2 having a good surface property, the water stopping property by the lip portion 4b is further improved. As a result, for example, even if the surface pressure is lowered, the water stoppage can be sufficiently maintained. Therefore, in this case, it is possible to make the outer diameter of the lip smaller,
This further facilitates insertion into the receptacle 2.

Further, when the connecting pipe 3 is displaced in the direction of pulling out from the receiving port 2, the packing 4 can be firmly attached to the connecting pipe 3. If the connection tube 3 is configured to be engaged in the direction to prevent withdrawal, the connection tube 3 can be prevented from coming off from the receiving port 2. In this case, the spigot 3a of the connection pipe 3 does not need to be subjected to any special processing for engaging the socket 2 in the axial direction. Therefore, a simpler configuration can be achieved, and good workability can be maintained because no additional work is required on site.

On the other hand, in the present embodiment, a retaining ring 5 formed in a ring shape is provided as a retaining means for engaging the packing 4 with the receiving port 2 in the axial direction as described above, and the cylindrical main body 6 is provided. Is also configured to function as a steady rest. That is, the cylindrical main body 6 is connected to the receiving port 2.
Is inserted into the space between the inner peripheral surface of the packing 4 and the cylindrical portion 4a of the packing 4, so that this space is made as small as possible over the entire circumference. As a result, pipe run-out in the receiving port 2 of the connecting pipe 3 is suppressed, and concentricity between the lip portion 4b and the receiving port 2 is maintained. A more uniform state over the circumference is ensured. As a result, it is possible to maintain better water stoppage.

In the above embodiment, an example in which the pipe joint of the present invention is applied to a drain pipe has been described, but the present invention can be applied to connection of any other pipe.

[0037]

As described above, in the pipe joint according to the first aspect of the present invention, the seal member interposed between the inner peripheral surface of the receiving port and the outer peripheral surface of the spout is expanded to the spout. It is formed in a shape having a substantially cylindrical main body fitted to the outside and an outer seal part protruding radially from the outer peripheral surface of the main body and pressed against the inner peripheral surface of the receiving port.

Therefore, by inserting the sealing member into the slot in advance and then inserting the sealing member into the socket, the insertion resistance caused by the elastic deformation of the outer seal portion at this time can be relatively suppressed. Therefore, the insertion operation can be easily performed. In addition, since the cylindrical main body is elastically deformed and fitted to the spigot, a stable sealing property is provided between the cylindrical main body by the elastic recovery force of the main body having a large contact area with the spigot. be able to. As a result,
The sealing property between the main body and the contact surface thereof can be improved with a simple configuration without separately providing a pressing member for compressing the main body in the axial direction, for example.

In the pipe joint according to the second aspect, a stopper for engaging the receiving port and the seal member in the axial direction is further provided, and the stopper prevents the sealing member from coming off from the receiving port. Is prevented. The detachment of the spigot from the seal member can be suppressed by the main body portion which is mounted on the spigot by being enlarged in diameter, so that the detachment of the second pipe from the receptacle is prevented. In this way, the spigot can be prevented from coming off without special processing for axially engaging the socket with the receiving port, and therefore, the structure for preventing the pipe from coming off is simpler. can do. In addition, since a configuration that does not require additional work on site can be adopted, good workability can be maintained.

In the pipe joint according to the third aspect, the outer seal portion is provided on the inner side in the axial direction of the main body portion, and the retaining means is provided with the main body portion closer to the receiving opening than the outer seal portion. Since it is made of a ring body with a substantially cylindrical anti-sway part inserted into the space between the inner peripheral surface of the receiving port, the space created in the receiving port becomes as small as possible. The tube runout is suppressed without separately providing the above member, and concentricity with the socket of the outer seal portion is maintained. Therefore, with a simpler configuration, it is ensured that the press-contact state of the outer seal portion against the inner peripheral surface of the receiving port becomes more uniform over the entire circumference, and as a result, it is possible to maintain better water stopping performance.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing a connected state of pipes using a pipe joint according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a shape of a pipe on a receiving port side of the pipe joint.

FIG. 3 is a partially cutaway front view showing a shape of a packing in the pipe joint.

FIG. 4 is a perspective view showing a shape of a retaining ring in the pipe joint.

FIG. 5 is a plan view of the retaining ring.

FIG. 6 is a sectional view taken along line X-O′-O-Y in FIG. 5;

FIG. 7 is an explanatory view showing an operation procedure of pipe connection using the pipe joint.

FIG. 8 is a cross-sectional view showing a shape of a packing used for a conventional pipe joint.

FIG. 9 is a cross-sectional view showing a connected state of pipes by a pipe joint in which the packing shown in FIG. 8 is interposed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Joint pipe (1st pipe) 2 Reception port 3 Connection pipe (2nd pipe) 3a Spout 4 Packing (seal member) 4a Cylindrical part (body part) 4b Lip part (outer seal part) 5 Retaining ring (Measuring means) 6 Cylindrical body (stabilizing part)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takeshi Ataka 7-1-22-2 Minamienkajima, Taisho-ku, Osaka City, Osaka Prefecture Inside Kubota Enkajima Plant Co., Ltd. (72) Inventor Yoshimichi Ogino Minami, Taisho-ku, Osaka-shi, Osaka 7-12-22 Enkajima Kubota Enkajima Plant

Claims (3)

[Claims] 1. A pipe joint in which a sealing member made of an elastic body is interposed between an inner peripheral surface of a receiving port of a first pipe and an outer peripheral face of a port of a second pipe inserted into the receiving port. The seal member has a substantially cylindrical main body part whose diameter is enlarged and fitted to the spout, and protrudes radially from the outer peripheral surface of a part of the main body part in the axial direction to the inner peripheral surface of the receiving port. A pipe joint characterized by being formed in a shape having an outer seal portion to be pressed. 2. The device according to claim 1, further comprising retaining means for axially engaging the receiving port and the sealing member so as to prevent the sealing member from being pulled out of the receiving port.
The described pipe fitting. 3. An outer seal portion is provided on an inner side in the axial direction of the main body portion, and the retaining means is provided between the main body portion and the inner peripheral surface of the receptacle opening end side of the outer seal portion. The pipe joint according to claim 2, comprising a ring body having a steadying portion inserted into said space.