JPS6114790Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a flexible detachment prevention pipe joint, and more particularly to a detachment prevention pipe joint that allows large bending when a bending force exceeding a predetermined value is applied.

In general, detachment prevention pipe joints are designed to allow slight bending between the socket and the inlet, but are not designed to allow large bends. However, when piping is installed in ground that is prone to uneven settlement, if large bends cannot be tolerated, there is a risk that excessive force will be applied to the pipe, deforming the pipe or damaging the pipe joint. Therefore, large bend-shaped pipe fittings with spherical rings are appropriately placed in such places, but they are expensive and it is difficult to use them in large numbers. There was a problem that occurred.

The purpose of this invention is to provide a separation-preventing pipe joint that allows large bending when excessive bending force is applied, and that can hold the piping path without allowing large bending until a bending force above a certain level is applied. A sealing material is interposed between the outer surface of the insertion port, a projection is provided on the outer surface of the insertion port at a position outside the socket end in the tube axis direction, and a locking ring that engages from the side opposite to the socket is inserted into the projection. A bolt is provided in the opening, one end of which engages with the socket and the other end of which extends through the locking ring, and the inner diameter of the bolt is located between the nut screwed onto the other end of the bolt and the locking ring. It is formed into a tubular shape that is set to be considerably larger than the outer diameter of the bolt and is fitted onto the bolt, and its compressive strength is set to be considerably smaller than the tensile strength of the bolt, so that there is no excessive force between the socket and the socket. A compressible member that is compressively deformed or damaged by the nut and the locking ring is interposed therein when a bending stress is applied thereto, and one embodiment thereof will be described below with reference to the drawings.

In Fig. 1, 1 is a socket, and 2 is a socket inserted into the socket 1, which comes into contact with an inner flange 3 for preventing the sealant from slipping out, which is protruded from the inner periphery of the opening end of the socket 1. An annular rubber sealing material 4 is interposed between the inner surface of the socket 1 and the outer surface of the socket 2. A sealing material 4 is provided on the inner surface of the socket 1 to prevent the sealing material 4 from being dragged toward the back of the socket when inserting the socket 2.
An annular protrusion 5 that fits into an annular groove 6 on the outer periphery is provided. Reference numeral 7 denotes a protrusion provided on the outer periphery of the open end of the socket 1, and a socket ring 8 that engages with the protrusion 7 from the side opposite to the open end of the socket holds the socket 1 at one end. This socket 1 is inserted through the socket of the tube body that it has.
is fitted externally. Instead of this socket ring 8, a flange may be provided protruding from the outer periphery of the socket 1. Bolt holes 9 are bored in the socket ring 8 at multiple locations in the circumferential direction. An annular projection 10 made of overlay welding is formed on the outer surface of the socket 2 at a position outward in the tube axis direction from the socket end. This protrusion 10 can also be formed by welding a ring. Reference numeral 11 denotes a circumferentially split lock ring having a diameter reducing force and fitted onto the socket 2 so as to engage the protrusion 10 from the side opposite to the socket 1. A tapered engagement surface 12 is formed that becomes smaller in diameter as it gets farther away from the surface. This lock ring 11 may be divided into two parts in the circumferential direction. Reference numeral 13 denotes a locking ring fitted onto the socket 2 so as to face the socket ring 8 in the tube axis direction, and the split lock ring 11 is attached to the inner circumference of the socket ring 8.
An engaging portion 15 that engages from the side opposite to the socket 1 is formed on the tapered engaging surface 12 of the socket ring 8, and the bolt hole 1 is located on the outer periphery in a position corresponding to the bolt hole 9 of the socket ring 8.
4 is drilled. The inner periphery of the engaging portion 15 has a width that has the same inclination as the tapered engaging surface 12 and allows the split locking ring 11 to engage with the split locking ring 11 over almost its entire width with a margin in the width direction. It has a tapered engagement surface 16. Note that the lock ring 11 can be omitted if the lock ring 13 is configured to be able to be divided into two in the circumferential direction. Reference numeral 17 denotes a claw-shaped bolt that is inserted into the bolt holes 9 and 14 and whose head is engaged with the socket ring 8.
3 further extends to the opposite side from the socket 1, and a nut 18 and a lock nut 19 are screwed into the tip thereof. There is a space between the locking ring 13 and the nut 18, and a tubular retractable member 20, such as a pipe made of polyvinyl chloride, is disposed so as to fit around the bolt 17. The inner diameter of the tubular retractable member 20 is set to be considerably larger than the outer diameter of the bolt 17, so that the retractable member 20 can be easily compressed and deformed. Moreover, the compressive strength of the compressible member 20 may be considerably smaller than the tensile strength of the bolt 17, and the material and shape of the compressible member 20 can be arbitrarily selected.

When joining, a sealing material 4 is attached to the inner surface of the socket 1, a socket ring 8 is fitted around the outer periphery of the socket 1, and a protrusion 1 is attached to the socket 2 to be inserted into the socket 1.
0, and externally fit the locking ring 13 and the split locking ring 11. Next, insert the socket 2 into the socket 1 in this state, and insert the socket ring 8 and the locking ring 13.
After inserting the bolt 17 into the bolt holes 9 and 14 and fitting the retractable member 20 from its tip, the socket ring 8 and the locking ring 13 are fastened together by screwing together the nut 18 and the lock nut 19. The bonding is thus completed. In this joined state, the space between the socket 1 and the socket 2 is reliably sealed by the sealing material 4 compressed between the inner surface of the socket 1 and the outside surface of the socket 2. The sealing material 4 comes off due to the pressure inside the pipe at the inner flange 3.
Since the seal material 4 is further compressed according to the pipe internal pressure, a seal surface pressure corresponding to the pipe internal pressure is always obtained. In addition, when a detachment force acts between the socket 1 and the socket 2, the socket 1 is removed from the socket ring 8.
The insertion port 2 has a protrusion 10 and a split lock ring 11.
Since the socket ring 8 and the locking ring 13 are connected by the bolt 17 and the nut 18 via the retractable member 20, the tension of the bolt 17 and the retractable member 20 Supported by the compressive force of , separation is reliably prevented. socket 1 and socket 2
If a detachment force larger than the proof strength of the retractable member 20 is applied during this period, the retractable member 20 will be deformed or damaged, and the socket 2 will further come out of the socket 1, thereby releasing the excessive load and preventing the engagement. The engagement between the retaining ring 13 and the nut 18 prevents the disengagement. Further, even when a bending force is applied between the receptacle 1 and the receptacle 2, the retractable member 20 is not deformed and the range of bending is limited while the bending force below a predetermined value is applied. However, when a bending force above a certain level is applied, a large compressive force is applied to the retractable member 20 fitted around the bolt 17 located on the tension side as shown in Fig. 2, causing compression deformation or breakage, and the corresponding The ring 8 and the locking ring 13 are greatly inclined to each other and are bent greatly between the socket 1 and the socket 2. Of course, once the nut 18 and the locking ring 13 are engaged, further bending or separation is prevented. In addition, when the insertion port 2 and the locking ring 13 are engaged, if a split locking ring 11 is inserted as in the embodiment, the locking ring 13 can be made into one piece, and the joining work at the site can be simplified. The locking ring 13 and the locking ring 1 can be separated easily and have the strength to withstand a large detachment force.
If 1 is engaged through the tapered engagement surfaces 12 and 16, compression force will be applied to the split lock ring 11 when a detachment force is applied, and even if the protrusion height of the protrusion 10 is low, only one Engagement with the split lock ring 11 is ensured, and even if there is some dimensional error in the outer diameter of the insertion port 2 or the inner diameter of the locking ring 13, reliable engagement can be achieved by simply changing the position of the locking ring 13. is ensured.

According to the flexible detachment prevention pipe joint of the present invention, as is clear from the above description, the other end of the bolt, one end of which engages with the socket, extends through the locking ring that engages with the socket. Since a retractable member is interposed between the locking ring and the nut screwed to the other end, the retractable member located on the tension side will be compressively deformed or damaged when excessive bending force is applied. As a result, the receiver
It bends significantly between the insertion ports, which prevents excessive force from being applied to the pipe body or pipe fitting, and even if a bending force below the specified level is applied, it will not inadvertently bend significantly and maintain the piping path normally. Of course, even if an excessive detachment force is applied, the pipe body and pipe fitting can be protected from deformation or damage of the retractable member, and complete detachment can be ensured by the engagement of the locking ring and nut. It can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the present invention, and FIG. 2 is a front view of the pipe joint in a greatly bent state. 1...Socket, 2...Socket, 4...Sealing material, 8
...Socket ring, 9, 14...Bolt hole, 10...
...Protrusion, 11... Lock ring, 12, 16...
Tapered engagement surface, 13...locking ring, 17...bolt, 18...nut, 19...lock nut.

Claims (1)

[Scope of utility model registration request] A sealing material is interposed between the inner surface of the receptacle and the outer surface of the receptacle, a projection is provided on the outer surface of the receptacle at a position outside the receptacle end in the tube axis direction, and the engagement is engaged with the projection from the side opposite to the receptacle. A retaining ring is placed on the socket, a bolt is provided whose one end engages with the socket and the other end extends through the retaining ring, and between a nut screwed onto the other end of the bolt and the retaining ring. , the inner diameter of the bolt is set to be considerably larger than the outer diameter of the bolt, and the compressive strength is set to be considerably smaller than the tensile strength of the bolt, and the socket is inserted. A flexible separation-preventing pipe joint characterized in that a retractable member is interposed which is compressively deformed or damaged by the nut and the locking ring when excessive bending stress is applied between the openings.