JPH0422154Y2 - - Google Patents

Description

[Detailed explanation of the invention] "Purpose of the invention" (Industrial application field) When a fluid transport pipe (for example, a water pipe, etc.) is buried in the soil, a vent pipe or a Significant bending loads and tensile loads act on transport pipes that are connected directly or in close proximity to valve bodies, etc., and transport pipes that are buried underground, such as roads.

The present invention relates to an expandable and flexible pipe joint that maintains the interconnected state of transport pipes, etc. in an expandable and flexible state, and prevents leakage of the transported fluid even when the above-mentioned bending loads and tensile loads are applied. It is something.

(Conventional flexible pipe joint) Figure 3 shows the revolutionary telescopic flexible pipe joint 1 (hereinafter simply referred to as FIG. 2 is an exploded perspective view of a pipe joint. The pipe joint 1 has a structure in which it can be expanded and contracted between a joint main body 2, which is an essentially necessary part, and a pipe retaining ring 5 that is fitted onto a transport pipe 8. This structure will now be explained along with the procedure for connecting it to the transport pipe 8.

First, the pipe retaining ring 5 is inserted into the pipe end of the transport pipe 8. The pipe retaining ring 5 has a part of its cylindrical circumference cut away, and its inner diameter elastically expands and contracts around the outer diameter of the transport pipe 8. The pipe retaining ring 5 is positioned at the end of the transport pipe 8 so as to provide a margin for insertion into the joint body 2. Diameter reducing joining pieces 5a, 5a protruding from both cut ends of the pipe retaining ring 5 toward the outer diameter direction. Therefore, both joint pieces 5a, 5a
When tightened with the bolt 7a and nut 7b, the pipe retaining ring 5 is reduced in diameter and firmly fixed to the transport pipe 8. Next, a push ring 3 having a round diamond-shaped plate shape and a seal ring 4 having a wedge-shaped cross section are inserted into the end of the transport pipe 8, and the end of the transport pipe 8 is inserted into the pipe of the joint body 2. Insert it into the insertion port 2b. The joint main body 2 is a short tube shaped like a drum with a bulge in the middle, and a flange 2a corresponding to the push ring 3 is formed on the outer periphery of the tube insertion port 2b. Then, the T-bolt 6 is inserted from the joint body 2 side toward the push ring 3 side, and the flanged cap nut 9 is screwed onto the male threaded end of the T-bolt 6. By the way, a retaining fin portion 5b is provided protrudingly on the outer circumferential surface of the pipe retaining ring 5.
A notch 5c was formed in b to allow the neck 9a of the flanged bag nut 9 to pass through, but to engage with the flange 9b. Therefore, as shown in FIG.
It is firmly connected by the fastening force. Due to this coupling, the seal ring 4 is compressed by the compression edge 3d formed on the coupling side surface of the push ring 3 and becomes smaller in diameter, so that the sealing to the transport pipe 8 is maintained. On the other hand, the pipe retaining ring 5 fixed to the transport pipe 8 is held such that its retaining fin portion 5b is movable between the collar portion 9b of the flanged bag nut 9 and the push ring 3. become. That is, the transport pipe 8 is flexibly connected to the joint body 2 within a range corresponding to the length of the neck portion 9a of the flanged cap nut 9.

(Problems to be Solved by the Invention) Materials for forming the transport pipe 8 include copper, steel, polyethylene, hard vinyl chloride, asbestos cement, and the like. Although the pipe fitting 1 could be extremely well connected to other transportation pipes except for pipes made of asbestos cement (hereinafter referred to as asbestos pipes), it cannot be used for asbestos pipes. It was hot. The reason is as follows.

FIG. 5 is a side sectional view showing the asbestos tube 8. FIG. Both ends 8a, 8a of the asbestos pipe 8 are connected to the pipe joint 1.
It has a narrow neck to serve as a connection to other things,
The necked part was finished with an accuracy of ±1mm. However, when burying the asbestos pipe 8 in the ground or performing repair work, it is necessary to adjust the length.
There was a case where it was cut at the midway portion 8b. The asbestos pipe 8 had poor dimensional accuracy except for its two end portions 8a, 8a, and a variation of +5 to -1 mm was allowed. For example, in a pipe with a nominal diameter of 100, both ends 8a and 8a are kept at φ123 to 125 mm, but the middle part 8b has a diameter of 123 to 129 mm.In the end, the asbestos pipe 8 has a diameter of 6 mm ranging from φ123 to 129 mm. This means that there are variations in the dimensions of the products. Therefore, even if the pipe retaining ring 5 (see Fig. 3) of the pipe joint 1 is inserted into the cut part (midway part 8b) of the asbestos pipe 8, when both the joint pieces 5a, 5a are tightened, However, the diameter of the pipe retaining ring 5 was not sufficiently reduced. As mentioned above, the pipe retaining ring 5 is structured to hold the neck portion 9a of the flanged bag nut 9 in the notch portion 5c of the retaining fin portion 5b when the diameter is reduced. If the amount is not sufficient, the inner surface of the notch 5c of the locking fin 5b will be damaged by the flanged bag nut 9.
or the flanged bag nut 9 could not be attached in the first place.
Such a problem occurs not only when the asbestos pipe 8 is cut at the midway part 8b, but also when the end 8a of the asbestos pipe 8 is inserted too deep into the joint body 2 due to a mistake on the part of the contractor. was also occurring. Note that asbestos pipes have been used customarily since ancient times, so their use was highest. Furthermore, it is inferior in strength to transport pipes made of other materials, and recently there has been concern about the pollution caused by the manufacturing process, so there is a trend to replace pipes with hard vinyl chloride pipes. Ta. Therefore, the above-mentioned problems frequently occur.

Furthermore, recently, corrosion-resistant coated transport pipes in which the outer circumferential surface of a steel pipe is lined with a resin material or the like have been developed. However, this type of coated transport pipe had a lining thickness of 1.5 mm or more, and its outer diameter was 3 mm or more larger than that of the steel pipe, so it had the same problems as the asbestos pipe. .

The present invention has been developed in view of the above-mentioned circumstances, and can be used even when the transport pipe is an asbestos-cement pipe.Moreover, when the pipe is made of a forming material other than asbestos-cement, the nominal diameter To provide a new telescopic flexible pipe joint (hereinafter referred to as the "proposed pipe joint") that can be used in common if the The purpose is to

``Structure of the invention'' (Means for solving the problem) The gist of the proposed pipe joint is that the pipe insertion port is a joint body comprising: a seal ring made of an elastic material attached to the opening circumference of the pipe insertion port in the joint body; and a compression lip facing the seal ring; A push ring connected by the above-mentioned bolts, a short cylindrical pipe retaining ring fitted to the pipe end of the transport pipe while maintaining the insertion allowance into the joint body, and a push ring bored in the push ring. a retainer comprising two or more seat plates corresponding to the insertion holes for the bolts, the retainers having adjacent seat plates connected to each other by a retainer rod constructed along the outer circumferential surface of the pipe retaining ring; The retaining tool has an expandable and flexible space formed between the retaining rod and the push ring, and a retaining piece protrudes from the seat plate portion to the side opposite to the installation side of the retaining rod. The pipe retaining ring is provided with a cutout part on a part of its circumference, the inner diameter of which is made larger than the outer diameter of the transport pipe, and both cut ends of the cutout part have an outer diameter. A connecting piece for diameter reduction is provided that extends in the direction, and engaging pieces are provided protruding from the outer circumferential surface of the retaining ring to correspond to the retaining rod and retaining piece of the retainer when the retainer is contracted. At the point.

(Function) As for the joint body, seal ring, and press ring that are originally necessary to form a telescopic flexible pipe joint, it is possible to use the same ones as conventional ones. Furthermore, the coupling between the joint body and the push ring is substantially the same as in the conventional art, and can be accomplished, for example, by fastening T-bolts and cap nuts. However, this bag nut is different from the conventional flange bag nut 9.
There is no need to use a flange like the one shown in Figure 3. These points are extremely beneficial in terms of facilitating the implementation of the proposed pipe joint.

The main characteristic of the proposed pipe joint is that the function that the conventional flanged bag nut 9 exerts due to the joint action of its neck 9a and flange 9b is separated into two functions. This is to prevent mutual interference. That is, one of the separated effects is
One function is to firmly connect the joint body and the push ring, and the other function is to hold the pipe retaining ring in a freely movable manner with respect to the joint body. This latter movement retaining action is achieved by the engagement between the retaining rod and retaining piece of the retainer fixed to the push ring and the engagement piece protruding from the outer circumferential surface of the pipe retaining ring. The retaining rod of the retainer is constructed so as to connect two or more seat plate portions that are adjacent to each other. Now, to explain the case where a retainer and a pipe retaining ring are combined, a retainer rod of the retainer is installed in a predetermined circumferential length area on the outer circumference of the retainer. . Furthermore, since the retaining piece of the retainer protrudes from the seat plate toward the side opposite to the installation side of the retainer rod, its protruding area can be increased to some extent. Therefore, when fixing the pipe retaining ring to the transport pipe, even if the diameter reduction amount does not reach a predetermined sufficient amount, the engaging piece of the pipe retaining ring will not displace the retaining rod and retainer of the retainer. securely engaged with the piece. On the contrary,
In the conventional flanged bag nut 9, it was not possible to unnecessarily increase the amount of protrusion of the flanged portion 9b. In this way, in the proposed pipe joint, it is possible to give a wide range to the outer diameter of the transport pipe to which the pipe retaining ring can be fixed, without requiring high dimensional accuracy for the engagement piece of the pipe retaining ring. becomes. On the other hand, the joint body, the push ring, and the retainer are closely connected to each other by fastening a T-bolt and a cap nut. In other words, the above-mentioned floating retaining action between the pipe retaining ring and the retaining tool does not directly affect the joint state of the joint body and push ring, and therefore the leakage prevention effect of the transported fluid is threatened. It's not something you can do.

(Example) The present invention will be described below based on drawings showing examples thereof.

FIG. 1 is an exploded perspective view showing the main parts of the proposed pipe joint. The proposed pipe joint is designed to allow mutual movement between the retainer 12 fixed to the push ring 3 and the pipe retaining ring 10 fitted to a transport pipe (not shown). It's getting old. The push ring 3 is connected to the flange 2a of the joint body 2 via the seal ring 4, similar to the conventional example shown in FIG.
It is connected to The proposed pipe joint allows the use of the joint body 2, seal ring 4, and press ring 3, which are essentially the same as those of the conventional pipe joint, which are essential for constructing a telescopic flexible pipe joint. This is the reason why the joint body 2 and the seal ring 4 are not shown in FIG. 1.

The embodiment shown in FIG. 1 is applied to a transport pipe (not shown) with a nominal diameter of 100 mm or less, and
There are two connection points between the push ring 3 and the joint body (not shown). That is, the fastening portions of the cap nut 13 used for the connection and the T-bolt 6 shown in FIG. 3 are arranged adjacent to each other.
Therefore, the removal stopper 12 of this embodiment has a seat plate portion 12.
c, 12c are provided in a symmetrical arrangement vertically,
Both seat plate portions 12c, 12c are connected to each other by a retaining rod 12b. The retaining rod 12b is
It is curved in an arc along the outer peripheral surface of the pipe retaining ring 10. Further, the retaining rod 12b is connected to the seat plate portion 12.
It is constructed so that it rises from c, and when the retainer 12 is brought into contact with the push ring 3,
A space for expansion and contraction is formed on the back side of the retaining rod 12b. An insertion hole 12d for inserting the T-bolt 6 (see FIG. 3) is provided in the center of the seat plate portion 12c. Also,
The removal stopper 12 has respective seat plate portions 12c, 12.
From c, retaining pieces 12a, 12a protrude toward the side opposite to the side on which the retaining rod 12b is installed. The retaining piece 12a is attached to the retaining rod 1.
2b, it is provided rising from the seat plate portion 12c, and therefore, an expandable/contractable space is also formed on the back side of the retaining piece 12a.

The main difference between the pipe retaining ring 10 of the proposed pipe joint and the conventional pipe retaining ring 5 (see Fig. 3) is as follows.
Instead of the locking fin portion 5b and the cutout portion 5c, a plurality of engaging pieces 11, 11, . . . are provided protrudingly provided at predetermined locations. The engaging pieces 11 engage with the retaining rods 12b and retaining pieces 12a on both sides of the stopper 12, centered on the seat plate 12c. That is, two engaging pieces 11 are arranged close to each other. The engagement piece 11 protruding from the outer peripheral surface of the pipe retaining ring 10 is positioned toward the back side of the retaining rod 12b and retaining piece 12a of the retainer 12 when the retaining ring 10 is reduced in diameter.
This is a position where the engaging pieces 11, 11 that are in close proximity to each other are housed closely together. That is, when both joint pieces 10a, 10a of the pipe retaining ring 10 are tightened with the bolt 7a and nut 7b to reduce the diameter of the pipe retaining ring 10, the circumferential portion is narrowed toward the joint pieces 10a, 10a. It becomes like this. Therefore, the engaging pieces 11, 11 are positioned so as to be slightly closer to the opposite side peripheral portions of the joining pieces 10a, 10a with respect to the pipe retaining ring 10 in a state where the diameter is not reduced. Note that the engagement piece 11
The external dimensions, protruding position, etc. do not require high dimensional accuracy. The reason is that the stopper 12
This is because the retaining rod 12b extends over approximately half of the outer peripheral surface of the pipe retaining ring 10, and the retaining piece 12a extends toward the remaining half of the outer peripheral surface of the retaining ring 10. This is because it protrudes, and the protruding area can be taken up to a certain extent. Therefore, the pipe retaining ring 1 including the engagement piece 11
It is no longer necessary to provide high precision in the entire zero, and the manufacturing cost can be extremely reduced. For example, the pipe retaining ring 10 is manufactured by casting, and the casting mold includes the center of the ring when the pipe retaining ring 10 is raised up, and the two joining pieces 1.
A split mold whose dividing plane is a plane passing through the middle of 0a and 10a can be used. Therefore, the number of lots that can be manufactured in one casting process increases,
Productivity becomes extremely high. Moreover, since the burrs generated after casting are only formed on the opposite side peripheries of the two joining pieces 10a, 10a, so as to draw the outline on the cross section, the work to remove them can be simplified. . On the other hand, the conventional pipe retaining ring 5 (see Fig. 3) has three or more retaining fins 5b and notches 5c when used for transport pipes with a nominal diameter exceeding 100 mm. Therefore, the casting mold had to be a split mold whose dividing surface is the bottom surface when the pipe retaining ring 10 is placed flat. This manufacturing method has low productivity, and since burrs are generated along the entire circumference of the ring, the workability for removing the burrs is also poor. In particular, it was very time-consuming because the burrs generated on the inner circumferential edge of the notch 5c in the hooking fin 5b had to be carefully removed.

FIG. 2 is a partially cutaway side view showing the state in which the proposed pipe joint is connected to the transport pipe 8. In the connection procedure of the proposed pipe joint, care must be taken when connecting the flange 2a of the joint body 2 and the push ring 3, in order to match the engagement piece 11 of the pipe retaining ring 10 fixed to the transport pipe 8. The main feature is that the stopper 12 is attached to the push ring 3 side. The removal stopper 12 has a bolt insertion hole 1 formed in its seat plate portions 12c, 12c.
2d is inserted into the male screw end of the T-bolt 6 protruding from the push ring 3 side, and further fixed by screwing the cap nut 13 into the male screw end. Note that the cap nut 13 is formed such that the length of the neck portion 13a exceeds the rising dimension of the retaining rod 12b or the retaining piece 12a of the retainer 12, and the head portion 13a for tool engagement is
b protrudes beyond the retainer 12. The fastening force between the T-bolt 6 and the cap nut 13 is the same as that of the joint body 2.
Since the flange 2a, push ring 3, and seat plate portion 12c of the retainer 12 are connected to each other without any gaps, the connected state is extremely strong. In addition, if an excessive tensile load or the like acts on the transport pipe 8, the engagement piece 11 of the pipe retaining ring 10 may become attached to the retaining rod 12b of the retainer 12.
Or, if an attempt is made to deviate from the elastic flexible space between the retaining piece 12a and the push ring 3, the engaging piece 11 of the pipe retaining ring 10, the retaining rod 12b of the retaining tool 12, or the retaining piece 12a first moves first. It becomes curved.
Therefore, even if an excessive tensile load as described above occurs, the state in which the seal ring 4 is compressed by the coupling of the joint body 2, push ring 3, and retainer 12 (leakage prevention effect of the transported fluid) is maintained. There is no immediate threat.

(Study of another embodiment) In the above embodiment, the transport pipe 8 has a nominal diameter smaller than 100 mm.
Since the description has mainly been given to the connection area between the flange 2a of the joint body 2 and the push ring 3,
However, when the nominal diameter of the transport pipe 8 exceeds 100, the number of joints increases to three or more. In the proposed pipe joint, the number of the stopper rods 12b in the stopper 12 may be increased or decreased depending on these aspects. Further, the retaining tool 12 is not limited to having the retaining rod 12b and the retaining piece 12a raised from the seat plate portion 12c. For example, the thickness of the seat plate portion 12c may be made thick so as to have the same dimension as the above-mentioned raised height, so that the retaining rod 12b, the seat plate portion 12c, and the retaining piece 12a are continuous on the same plane. good. In this case, the neck portion 13a of the cap nut 13 is also unnecessary. In this way, the configuration and shape of the proposed pipe joint can be changed as appropriate depending on the embodiment.

"Effects of the Invention" As is clear from the above explanation, according to the telescopic flexible pipe joint of the present invention, when the pipe retaining ring is fixed to the transport pipe, the diameter of the retaining ring is reduced by a predetermined amount. Even if a sufficient amount is not reached, the engaging piece of the pipe retaining ring is configured to reliably engage with the retaining rod and retaining piece of the retainer. Therefore, when the transport pipe is an asbestos cement pipe, the pipe can be reliably connected regardless of whether the pipe retaining ring is fitted at the pipe end or in the middle. Of course, the same applies to coated transport pipes in which steel pipes are lined with resin. In addition, in the proposed pipe joint, the same ones as conventional ones can be used for the joint main body, seal ring, and press ring that are originally necessary for constructing a telescopic flexible pipe joint. Therefore, the present invention can be easily applied to conventional pipe joints that are stocked or already installed at retailers, construction companies, etc., by simply providing pipe retaining rings and retainers. Moreover, the pipe retaining ring of the proposed pipe joint has many excellent advantages, such as high productivity and the ease of manufacturing work, which can significantly reduce manufacturing costs. There is.

[Brief explanation of the drawing]

Figure 1 is an exploded perspective view showing the main parts of the proposed pipe joint, Figure 2 is a partially cutaway side view showing the state in which the proposed pipe joint and the transport pipe are connected, and Figure 3 is a conventional pipe joint. FIG. 4 is a partially cutaway side view showing a state in which a conventional pipe joint and a transport pipe are connected, and FIG. 5 is a side sectional view showing an asbestos cement pipe. 2... Joint body, 2b... Pipe insertion port, 3... Push ring, 4... Seal ring, 10... Pipe retaining ring,
10a... Joint piece, 11... Engaging piece, 12... Removal stopper, 12a... Removal prevention flange, 12b... Removal prevention rod,
13... Fukuro Natsuto.

Claims (1)

[Scope of utility model registration request] A telescopic flexible pipe joint that connects fluid transport pipes buried in soil, etc., includes a joint body with a pipe insertion port, and an elastic material that is attached to the periphery of the opening of the pipe insertion port in the joint body. a seal ring, a press ring having a compression edge facing the seal ring and connected around the pipe insertion opening of the joint body by two or more bolts, and a press ring that is inserted into the pipe end of the transport pipe into the joint body. A short cylindrical pipe retaining ring that is fitted while retaining a margin, and two or more seat plate portions corresponding to bolt insertion holes drilled in the push ring, and an outer periphery of the pipe retaining ring. It consists of a retaining tool in which adjacent seat plate parts are connected to each other by a retaining rod installed along the surface, and a space for expansion and contraction is formed between the retaining rod and the push ring. At the same time,
A retaining piece is provided on the seat plate portion to protrude to the side opposite to the installation side of the retaining rod, and the pipe retaining ring has a cutout part on a part of the circumference so that the inner diameter thereof is the same as the outer diameter of the transport pipe. The diameter is expanded to a larger diameter than the pipe diameter, and both cut ends of the cut-out portion are provided with diameter-reducing joining pieces directed toward the outer diameter direction, and the outer circumferential surface of the pipe retaining ring has the aforementioned diameter-reducing joint pieces when the diameter is reduced. A telescoping flexible pipe joint characterized in that engaging pieces are provided in a protruding manner corresponding to each of the retaining rod and the retaining piece of the retainer.