JP2005337269A - Separation preventing pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe joint, reducing the diameter of a lock ring to engage with the projecting part of a spigot in a simple structure. <P>SOLUTION: In this pipe joint of pipes jointed to each other, the spigot 4 formed at the end of one pipe 3 is inserted in the interior of a socket 2 formed at the end part of the other pipe 1. In the pipe joint, the lock ring 17 mounted in the inner periphery of the socket 2 and the projecting part 21 formed in the outer periphery of the spigot 4 are engaged with each other to prevent the spigot 4 from slipping out of the socket 2 and to perform outer fitting of a pressure ring 25 to the lock ring 17. The pressure ring 25 comes into contact with the inner peripheral surface of the socket 2 at two or more first specified parts thereof along the circumferential direction, and presses the lock ring 17 inward in the radial direction at two or more second specified parts 27 thereof along the circumferential direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a separation preventing pipe joint.

  As a joint between cast iron pipes, there is a pipe joint having a receiving structure in which an insertion opening formed at the end of the other pipe is inserted into the receiving opening formed at the end of one of the pipes to be joined together. Are known. As one type of such a pipe joint, a detachment prevention pipe joint that prevents the insertion port from coming out from the receiving port is often used. Although it is known as an earthquake-resistant joint that prevents the insertion opening from being removed from the receiving opening and allows a predetermined amount of expansion and contraction between the receiving openings, this specification also includes a seismic coupling. Treat as.

  As a detachment prevention fitting, the protrusion formed on the outer periphery of the insertion port engages with the lock ring mounted on the inner periphery of the reception port from the back side of the reception port, thereby removing the insertion port from the reception port. The prevention is described in, for example, Patent Document 1. In addition to the one described in Patent Document 1, instead of forming a clear protrusion on the outer periphery of the insertion port, an annular groove is formed on the outer periphery of the insertion port, and the lock ring is fitted into the annular groove. Similar effects can be obtained. In this case, it can be considered that the protrusion is formed by the side wall of the annular groove, and in the present specification, such a protrusion is also handled as the protrusion.

  In such a detachment prevention pipe joint, when the insertion port is inserted into the receiving port, the protruding portion of the insertion port must be sent to the back side of the receiving port rather than the lock ring. For this reason, when the insertion port is inserted into the receiving port, the inner diameter of the lock ring must be larger than the outer diameter of the protrusion. On the other hand, after the protrusion enters the back side of the receiving port from the lock ring, the inner diameter of the lock ring is smaller than the outer diameter of the protrusion in order to engage the protrusion with the lock ring. There must be.

In order to satisfy this contradictory condition, in the one described in Patent Document 1, the lock ring is given elasticity in the spreading direction, and its inner diameter is larger than the outer diameter of the protrusion so as to allow passage of the protrusion. After the projection has passed through the inside of the lock ring, the outer surface of the lock ring is calibrated by a set bolt that is screwed from the outer surface of the receptacle so as to penetrate the wall of the receptacle in the radial direction. The lock ring is deformed so that the inner diameter thereof is smaller than the outer diameter of the protrusions by pressing inward in the direction to reduce the diameter of the lock ring.
Japanese Utility Model Publication No. 61-200981

  However, in the case of using the set bolt in this way, the inner screw must be machined in the receiving port, so that the structure of the joint becomes complicated. In addition, there is no problem if the sealing material between the receptacle insertion holes is located behind the set bolt as in the case of Patent Document 1, but the set bolt is on the other side than the seal material. In the case of being located on the side, it is necessary to seal between the set bolt and the internal thread of the receiving port, and the structure of the joint is complicated also from this point.

  Therefore, the present invention inserts the insertion port formed at the end of the other tube into the reception port formed at the end of one tube to be joined to each other, and attaches it to the inner periphery of the reception port. The lock ring is connected to the insertion projection with a simple structure in a pipe joint that prevents the insertion of the insertion port from the receiving port by engaging the formed lock ring with the projection formed on the outer periphery of the insertion port. It is an object of the present invention to make it possible to reduce the diameter for engagement.

  In order to achieve this object, the present invention provides a pipe joint in which an insertion opening formed at the end of the other pipe is inserted into a receiving opening formed at the end of one of the pipes joined together. The lock ring mounted on the inner periphery of the receiving port and the protrusion formed on the outer periphery of the insertion port engage with each other to prevent the insertion port from coming out of the receiving port. The pressing ring is in contact with the inner peripheral surface of the receiving port at a plurality of first specific portions along the circumferential direction, and at the same time, the lock ring is radially inward at the plurality of second specific portions along the circumferential direction. It is configured to press in the direction.

  According to such a configuration, the lock ring can be reliably pressed inward in the radial direction with a simple structure that does not use a set bolt. In order to allow the insertion protrusion to pass inside the lock ring, for example, the second specific portion of the pressing ring may be elastically deformed to expand the diameter together with the lock ring, and the operation is easy.

  In FIG. 1, a receiving opening 2 is formed at the end of one cast iron pipe 1 to be joined to each other, and an insertion inserted into the receiving opening 2 is inserted into the end of the other cast iron pipe 3. A mouth 4 is formed. A lining layer 5 is formed on the inner periphery of the tubes 1 and 3.

  An annular sealing material accommodation recess 6 is formed on the inner periphery of the receiving port 2 in the vicinity of the opening end. Reference numeral 7 denotes the bottom surface, which forms a sealing material pressure contact surface. 8 is the back end surface, and is formed in the pipe diameter direction. An annular protrusion 9 is formed on the inner periphery of the receiving port 2 on the inner side of the sealing material receiving recess 6, and an annular lock link is received on the inner periphery of the receiving port 2 on the inner side of the annular protrusion 9. A recess 10 is formed. At the end of the lock ring housing recess 10 on the receiving opening side, a tapered surface 11 having a gradually decreasing diameter toward the receiving opening side is formed. Reference numeral 12 denotes a rear end surface of the lock ring housing recess 10 which is formed in the pipe diameter direction. Reference numeral 13 denotes a bottom surface of the lock ring housing recess 10, which is formed in the tube axis direction.

  A rubber-like annular sealing material 14 is accommodated in the sealing material accommodating recess 6. In addition, a metal-made press ring 15 divided in the circumferential direction is disposed in the sealing material receiving recess 6, and the end portion of the bolt 16 in the tube axis direction is screwed out from a plurality of positions along the circumferential direction of the press ring 15. Presses the back end surface 8 of the sealing material accommodation recess 6, thereby compressing the sealing material 14 between the outer peripheral surface of the insertion opening 4 and the bottom surface 7 of the sealing material accommodation recess 6 by the pusher wheel 15, thereby providing a predetermined seal. It is configured to demonstrate performance.

  The lock ring housing recess 10 houses a metal circumferentially divided lock ring 17. The lock ring 17 has a substantially rectangular cross section and an outer peripheral tapered surface 18 that can contact the tapered surface 11 of the housing recess 10. Reference numeral 19 denotes an outer peripheral surface of the lock ring, which is formed in the tube axis direction. In the insertion opening 4, an annular groove 20 is formed on the outer periphery of the portion corresponding to the lock ring housing recess 10, and thereby, an annular protrusion is formed on the outer periphery of the insertion opening 4 on the tip side of the annular groove 20. 21 is formed. The annular groove 20 is formed so that the groove width along the tube axis direction is sufficiently larger than the width of the lock ring 17 along the tube diameter direction. The lock ring 17 is formed so as to have an elastic force in the diameter reducing direction, and is fitted into the annular groove 20.

  With the lock ring 17 fitted in the annular groove 20 as described above, a space 22 is formed between the outer peripheral surface 19 of the lock ring 17 and the bottom surface 13 of the receiving recess 10.

  As shown in FIGS. 1 and 2, a pressing ring 25 is disposed in the space 22. The pressing ring 25 is formed of, for example, a stainless steel thin plate so as to have radial elasticity, and is constituted by an annular body that is continuous in the circumferential direction. The pressing ring 25 has a large-diameter portion 26 as a first specific portion formed at a plurality of positions along the circumferential direction, and the second large-diameter portion 26, 26 is adjacent to the second large-diameter portion 26. A lock ring pressing portion 27 as a specific portion is formed at an inner position along the radial direction than the large diameter portion 26. The large-diameter portion 26 is configured to be in contact with the bottom surface 13 of the lock ring housing recess 10, and the lock ring pressing portion 27 is in contact with the outer peripheral surface 19 of the lock ring 17 to press the outer peripheral surface 19 inward in the radial direction. Is configured to do. The pressing ring 25 having the large-diameter portion 26 and the lock ring pressing portion 27 has, for example, a plurality of positions along the circumferential direction in a ring body formed with the size of the large-diameter portion 26 over the entire circumference. Can be obtained by forming the lock ring pressing portion 27 by plastic deformation inward.

  A method of joining the receiving port 2 and the insertion port 4 will be described. First, as shown in FIG. 3, the seal member 14 and the push ring 15 with the bolt 16 are accommodated in the accommodating recess 6 of the receiving port 2, and the pressing ring 25 and the lock ring 17 are accommodated in the accommodating recess 10. At this time, the lock ring 17 is disposed in the vicinity of the back end surface 12, and the pressing ring 25 is disposed in the vicinity of the tapered surface 11 so that the large-diameter portion 26 is in contact with the bottom surface 13 of the housing recess 10. That is, the pressing ring 25 is held by the housing recess 10 in a state of being centered with respect to the receiving port 2.

  In this state, as shown in FIG. 3, the insertion opening 4 is inserted into the receiving opening 2. Then, first, the protrusion 21 of the insertion port 4 enters the inner periphery of the sealing material 14. Therefore, the bolt 16 is unscrewed from the push wheel 15 and its end is brought into contact with the back end surface 8 of the housing recess 6. In addition, the tip of the press wheel 15 is brought into contact with the sealing material 14. When the bolt 16 is further unscrewed from the pusher wheel 15 in this state, the sealing material 14 is compressed between the bottom surface 7 of the housing recess 6 and the outer peripheral surface of the insertion opening 4, that is, the outer surface of the projection 21 by the pusher wheel 15. The seal function can be demonstrated.

  Next, as shown in FIG. 4, the insertion port 4 is further inserted into the back side of the receiving port 2, and stopped before the lock ring 17, that is, the back end surface 12. Then, while expanding the diameter of the lock ring 17, an operator in the pipe fits the lock ring 17 to the projection 21 of the insertion slot 4 and further pushes the lock ring 17 in the direction of the pipe axis as shown in FIG. Then, this is fitted into the pressing ring 25. At this time, the lock ring 17 is fitted into the pressing ring 25 while the pressing portion 27 of the pressing ring 25 is elastically expanded by the action of the outer peripheral tapered surface 18 of the locking ring 17.

  Then, when the lock ring 17 is further moved in the tube axis direction in this state, the lock ring 17 fits into the annular groove 20 of the insertion port 4 while elastically reducing the diameter, as shown by a virtual line in FIG. The pressing ring 25 tries to return to the original posture by displacing the pressing portion 27 inward in the radial direction following the diameter-reducing operation of the lock ring 17, thereby causing the lock ring 17 to have a diameter as shown in FIG. 2. It will press inward in the direction. When the lock ring 17 is fitted into the annular groove 20, the insertion of the insertion opening 4 is stopped in a state where the protrusion 21 is located at an appropriate position between the tapered surface 11 and the back end surface 12 of the housing recess 10.

  With the pipe joint having such a configuration, the lock ring 17 can be reliably pressed against the annular groove 20 of the insertion opening 4 by the action of the pressing ring 25. For this reason, until the front end of the insertion port 4 hits the rear end surface 12 of the receiving recess 10 of the receiving port 2 or until the outer peripheral tapered surface 18 of the lock ring 17 engaged with the protrusion 21 hits the tapered surface 11 of the receiving recess 10. In the range, the expansion / contraction function between the receiving opening and the separation preventing function are exhibited, and thereby a predetermined earthquake resistance function can be exhibited. At this time, the lock ring 17 can be reliably pressed radially inward by the pressing ring 25 with a simple structure without using a set bolt.

  Further, as described above, the outer peripheral taper surface 18 of the lock ring 17 hits the taper surface 11 of the housing recess 10, so that the lock ring 17 can be pressed more firmly in the radial direction, and a more reliable detachment prevention function. Can be demonstrated.

  FIG. 6 shows a separation preventing pipe joint according to another embodiment of the present invention. Here, an annular protrusion 21 is formed on the outer periphery of the distal end of the insertion port 4, the receiving recess 10 of the receiving port 2 is formed with a width corresponding to the lock ring 17, and is inserted into the inner periphery of the opening end of the receiving port 2. The seal member 14 is disposed between the outer periphery of the port 4 and the press ring 32 is fastened with a plurality of bolts 30 and nuts 31 in the tube axis direction in the circumferential direction screwed into the end portion of the receiving port 2. The pusher 32 is configured to compress the sealing material 14. Reference numeral 25 denotes a pressing ring.

  FIG. 7 shows a detachment prevention pipe joint according to still another embodiment of the present invention. Here, the accommodating recess 10 and the annular groove 20 are formed to have a width corresponding to the lock ring 17, the sealing material 14 is provided on the back side of the receiving port with respect to the lock ring 17, and the tip of the insertion port 4 and the receiving port 2. A push ring 15 capable of screwing out the bolt 16 is provided between the rear end. Reference numeral 25 denotes a pressing ring.

  FIG. 8 shows a detachment prevention pipe joint according to still another embodiment of the present invention. The configuration shown in FIG. 8 is the same as that shown in FIG. 7, but on the outer periphery of the insertion port 4, in place of the annular groove 20 of FIG. A protrusion 21 is formed at a distance. Reference numeral 25 denotes a pressing ring. The seal member 14 and the pusher wheel 15 from which the bolt 16 can be screwed out are provided at a position on the back side of the receiving port 2 with respect to the protrusion 21.

  FIG. 9 shows a separation preventing pipe joint according to still another embodiment of the present invention. Here, the sealing material 14 is compressed in the radial direction between the inner peripheral surface of the receiving port 2 and the outer peripheral surface of the insertion port 4 so as to exhibit a predetermined sealing function. The lock ring 17 is housed in the housing recess 10 formed on the inner periphery of the receiving port on the back side of the seal material 14. The protrusion 21 of the insertion opening 4 has a tapered surface 33 formed at the tip thereof, and this tapered surface 33 cooperates with the tapered surface 34 formed on the inner periphery of the lock ring 17 to divide it into one circumferential direction. By elastically expanding the diameter of the lock ring 17, the protrusion 21 can pass through the inside of the lock ring 17 toward the back side of the receiving port 2. Reference numeral 25 denotes a pressing ring.

  FIG. 10 shows a detachment prevention pipe joint according to still another embodiment of the present invention. Here, the sealing material 14 exhibits a predetermined sealing function by being compressed in the radial direction between the inner peripheral surface of the receiving port 2 and the outer peripheral surface of the insertion port 4 in the same manner as shown in FIG. 9. It is configured as follows. The lock ring 17 is disposed closer to the opening side of the receiving port 2 than the seal material 14 and is accommodated in the accommodating recess 10 having a width corresponding to the lock ring 17. Reference numeral 25 denotes a pressing ring. The annular groove 20 of the insertion opening 4 is formed with a width larger than that of the lock ring 17, and is configured to exhibit an expansion / contraction function between the reception opening insertion openings, that is, an earthquake resistance function.

It is a longitudinal cross-sectional view of the separation preventing pipe joint according to the embodiment of the present invention. It is a cross-sectional view of the separation preventing pipe joint of FIG. It is sectional drawing which shows the joining process of the pipe joint of FIG. FIG. 4 is a cross-sectional view showing a step subsequent to FIG. 3. FIG. 5 is a cross-sectional view showing a step subsequent to FIG. 4. It is sectional drawing of the separation prevention pipe joint of other embodiment of this invention. It is sectional drawing of the detachment prevention pipe joint of other embodiment of this invention. It is sectional drawing of the detachment prevention pipe joint of other embodiment of this invention. It is sectional drawing of the detachment prevention pipe joint of other embodiment of this invention. It is sectional drawing of the detachment prevention pipe joint of other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 One pipe 2 Receiving port 3 Other pipe 4 Insertion 17 Lock ring 20 Annular groove 21 Protrusion 25 Press ring 26 Large diameter part 27 Lock ring press part

Claims (1)

  A pipe joint in which an insertion port formed at the end of the other pipe is inserted inside a receiving port formed at the end of one of the pipes to be joined to each other, and is attached to the inner periphery of the receiving port. The locking ring and the protrusion formed on the outer periphery of the insertion port are engaged with each other, so that the insertion port is prevented from coming out of the receiving port, and the pressing ring is fitted to the locking ring. A plurality of first specific portions along the circumferential direction are in contact with the inner peripheral surface of the receiving port, and a plurality of second specific portions along the circumferential direction are configured to press the lock ring radially inward. Detachment prevention pipe joint characterized by the above.

Images