JP5514414B2 - Plug-in fittings - Google Patents

Description

  The present invention relates to a plug-in type pipe joint that can be connected in a seal-like manner by simply inserting a connection pipe through which underground power or communication cables are passed, or a connection pipe used for water supply piping.

  As this type of plug-in type pipe joint, for example, those shown in FIGS. 8 and 9 are known (see, for example, Patent Documents 1 and 2). The insertion-type pipe joint has a receiving opening 22 into which the end of the connecting pipe P is inserted at both ends in the axial center direction of the cylindrical fitting body 21, and a rubber packing (lip (Packing) 23, and a lock ring 24 and a support elastic ring 28 arranged on the inner back side from the packing 23 are incorporated, and the inner diameter is narrowed slightly to the inner back portion from the lock ring 24 of the joint body 21. The pipe end stopper 25 is provided. A packing fitting groove 26 into which the packing 23 is fitted is formed at a position where the packing 23 on the inner peripheral surface of the receiving port 22 is located, and the lock ring 24 and the supporting elastic ring 28 on the inner peripheral surface of the receiving port 22 are formed. A ring fitting groove 27 having a constricted and tapered pressing surface 27a is formed at the position. When the connection pipe P is connected, the end of the connection pipe P is inserted from the receiving port 22 until it abuts against the pipe end stopper 25, and the packing 23 is in close contact with the outer peripheral surface of the connection pipe P to be sealed in an airtight manner. When the connecting pipe P moves in the withdrawal direction, the lock ring 24 comes into contact with the taper-shaped pressing surface 27a to reduce the diameter, so that the outer peripheral surface of the connecting pipe P is strongly bitten and the connecting pipe P is prevented from being removed. It is like that.

JP 2001-241580 A JP 2001-227688 A

  However, in the plug-in type pipe joint, as shown in FIG. 9, the groove side wall 26 a on the upstream side in the connecting pipe insertion direction in the packing fitting groove 26 rises vertically from the groove bottom 26 b of the packing fitting groove 26. The end face 23a on the upstream side in the connecting pipe insertion direction of the packing 23 is formed vertically corresponding to the vertical groove side wall 26a. For this reason, when water-stopping performance test or gas leakage inspection of the packing 23 is performed, or when power or communication cables are passed through the connection pipe P by applying air pressure, the packing air is sealed by the air (high pressure) in the connection pipe P. 11 is pushed in the packing fitting groove 26 in the direction A on the upstream side of the connecting pipe insertion direction as shown in FIG. Thereby, the clearance gap between the inner periphery of the opening tip part 22a of the receptacle 22 and the outer periphery of the connection pipe P along the round R which the edge part 23a1 of the connection pipe insertion direction upstream of the packing 23 is attaching to the groove side wall 26a I sometimes squeezed out. The protruding packing 23 does not return to the original position. The sticking out of the packing 23 causes a problem that the sealing effect is reduced or lost.

  The present invention has been made to solve such a problem, and the object of the present invention is to fit the packing into the packing fitting groove provided on the inner periphery of the joint body as described above. An object of the present invention is to provide a plug-in type pipe joint that can reliably prevent the packing from protruding from the packing fitting groove by devising the cross-sectional shape of the packing or packing fitting groove in the plug-in type pipe fitting.

As described in claim 1, the present invention will be described with reference to the reference numerals attached to FIG. 1 to FIG. 7. A joint body having a receiving port (7) into which an end of a connecting pipe (P) is inserted ( 1) An annular packing fitting groove (9) is provided on the inner periphery of the receiving port (7). The outer periphery of the end of the connecting pipe (P) and the receiving port (7) are provided in the packing fitting groove (9). In the plug-in type pipe joint in which the packing (2) for sealing between the inner periphery is fitted, it faces the groove side wall (9b) on the upstream side in the connecting pipe insertion direction in the packing fitting groove (9). The end surface (2c) of the packing (2) is formed into a tapered surface (5) that is gradually narrowed toward the downstream side in the connecting pipe insertion direction, and the packing (2) is connected to the ring-shaped portion (2a), A lip packing having a lip portion (2b) projecting radially inward from the inner periphery of the ring-shaped portion (2a), The distance between the groove side wall (9b) on the upstream side in the connecting pipe insertion direction in the packing fitting groove (9) and the end surface (2c) of the packing (2) facing the groove side wall (9b) is from the center of the joint body (1). It is characterized by being different according to the distance.

  According to the above configuration, the packing (2) is pushed and moved in the direction A on the upstream side of the connecting pipe insertion direction in the packing fitting groove (9) by the air enclosed in the connecting pipe (P) at the time of gas leakage inspection, At this time, the end face (2c) on the upstream side in the connecting pipe insertion direction of the packing (2) abuts on the groove side wall (9b) on the upstream side in the connecting pipe insertion direction of the packing fitting groove (9). 2) Since the end on the upstream side in the connecting pipe insertion direction is pushed in the bottom direction of the packing fitting groove (9), that is, in the anti-extrusion direction, the packing (2) protrudes from the packing fitting groove (9). Can be surely prevented.

  Even if the water flowing in the joint body (1) flows into the packing (2) from between the inner periphery of the joint body (1) and the outer periphery of the connection pipe (P), the water pressure causes the lip portion (2b) to flow. A seal pressure is generated by pressing against the outer peripheral surface of the connection pipe (P). Therefore, the seal function is effectively exhibited by the single packing (2). Further, the lip portion (2b) of the packing (2) can be easily deformed by a sliding contact action with the outer peripheral surface of the connection pipe (P) with a small insertion load of the connection pipe (P). P) is easy to insert.

  According to the present invention, the end surface facing the groove side wall of the packing is formed into a tapered surface gradually narrowing toward the downstream side in the connecting pipe insertion direction, and is protruded from the packing fitting groove of the packing. This is advantageous in that it can be surely prevented and sealing performance can be secured.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a plug-in pipe joint according to an embodiment of the present invention in a state where a connecting pipe is completely inserted, FIG. 2 is an enlarged cross-sectional view of a packing accommodating portion in the plug-in pipe joint of FIG. 1 is a partial cross-sectional view of the packing in the plug-in type pipe joint of FIG. 1, and FIG. 4 is a cross-sectional view showing a state in which the packing in the packing housing portion in the plug-in type pipe joint of FIG. It is.

  The plug-in type pipe joint shown in FIG. 1 includes a joint body 1, a packing 2, a lock ring 3, and a support elastic ring 4.

  The joint body 1 is made of metal and is formed into a cylindrical shape, and the outer periphery thereof is integrally covered with a corrosion-proof cylindrical body 6 made of a resin such as polyethylene. This joint main body 1 has an opening 7 into which the end of the connecting pipe P is inserted at both axial end portions thereof, and the pipe end stopper portion 8 is connected to the joint main body 1 in such a manner that the portion is narrowed in the vicinity of the center in the axial direction. Provided integrally. Both ends 6a, 6a in the axial direction of the anticorrosion cylinder 6 project outward in the axial direction from both ends in the axial direction of the joint body 1 to open the opening tip 7a of the receiving port 7, and inside the opening tip 7a A packing fitting groove 9 is formed. An intermediate portion between the packing fitting groove 9 and the pipe end stopper portion 8 of the joint body 1 bulges radially outward to form a ring fitting groove 10 on the inner periphery of the portion.

  As shown in FIG. 2, the packing fitting groove 9 includes a flat groove bottom wall 9a, a groove side wall 9b on the upstream side in the connecting pipe insertion direction on the groove bottom wall 9a, and a groove side wall 9c on the downstream side in the connecting pipe insertion direction. It is formed in the cross-sectional square shape which has. As shown in FIG. 1, the groove side wall of the ring fitting groove 10 on the upstream side in the connecting pipe insertion direction is formed with a tapered surface 10a that is gradually narrowed toward the upstream side in the connecting pipe insertion direction.

  Thus, the packing 2 is fitted into the packing fitting groove 9 of the joint body 1. As shown in FIG. 3, the packing 2 includes a ring-shaped portion 2 a and one or more lip portions 2 b that protrude integrally from the inner periphery of the ring-shaped portion 2 a in the radial direction. Molded with synthetic rubber or synthetic resin. As shown in FIGS. 2 and 3, both end faces 2c and 2d of the ring-shaped portion 2a facing the groove side walls 9b and 9c of the packing fitting groove 9 or at least one end face 2c facing the groove side wall 9b are inserted into the connecting pipe. The tapered surface 5 is gradually narrowed toward the downstream side. The distance between the groove side wall (9b) on the upstream side in the connecting pipe insertion direction in the packing fitting groove (9) and the end surface (2c) of the packing (2) facing the groove side wall (9b) is the center of the joint body (1). Depending on the distance from. The tapered surface 5 has, for example, an angle θ (see FIG. 3) formed by the vertical end surfaces 2c and 2d of the ring-shaped portion 2a of 10 degrees. The ring fitting groove 10 is fitted in a state where the lock ring 3 is received and supported by the supporting elastic ring 4 so as to face the tapered surface 10a.

  When connecting the connecting pipe P, as shown in FIG. 1, the connecting pipe P is inserted into the receiving port 7 at one end in the axial direction of the joint body 1 until the end of the connecting pipe P comes into contact with the pipe end stopper portion 8. Although not shown, the end of another connecting pipe P is similarly inserted into the receiving port 7 at the other axial end of the joint body 1.

When the end of the connecting pipe P is inserted into the joint 7 at the receiving end 7 of the joint body 1 until it contacts the pipe end stopper 8, the lip 2b of the packing 2 is formed on the outer peripheral surface of the end of the connecting pipe P as shown in FIG. In close contact with the compression, the packing 2 hermetically seals the space between the inner peripheral surface of the receiving port 7 and the outer peripheral surface of the end portion of the connecting pipe P. When the lip portion 2b of the packing 2 is in compression in close contact with the outer peripheral surface of the connecting pipe P with the lip portion 2b facing inward in the joint main body 1, water flowing in the joint main body 1 Even if it flows into the packing 2 from between the end portions of the connecting pipe P, a sealing pressure is generated by pressing the lip 2b against the outer peripheral surface of the connecting pipe P due to the water pressure. Demonstrate the function effectively. Further, since the lip portion 2b of the packing 2 can be easily deformed by a sliding contact action with the outer peripheral surface of the connection pipe P with a small insertion load of the connection pipe P, the connection pipe P can be easily inserted.
When the end of the connection pipe P is inserted into the receiving port 7 of the joint body 1 until it contacts the pipe end stopper 8, the inner periphery of the lock ring 3 is the outer peripheral surface of the end of the connection pipe P as shown in FIG. Engage lightly and engage. When the connecting pipe P is pulled in the extraction direction (counter-insertion direction), the outer peripheral surface of the lock ring 3 that moves in the same direction together with the connecting pipe P comes into contact with the tapered surface 10 a of the ring fitting groove 10. The diameter is reduced, and the biting into the outer peripheral surface of the connecting pipe P is increased, so that the end of the connecting pipe P can be prevented from coming out of the receiving port 7.

  At the time of gas leakage inspection etc., the packing 2 is pushed and moved in the packing fitting groove 9 in the packing fitting groove 9 as shown in FIG. At this time, the end surface 2c on the upstream side in the connecting pipe insertion direction of the packing 2 forms a tapered surface 5 gradually narrowing toward the downstream side in the connecting pipe insertion direction, and the packing (2) is connected to the ring-shaped portion (2a). A lip packing having a lip portion (2b) projecting radially inward from the inner periphery of the ring-shaped portion (2a), and a groove on the upstream side in the connecting pipe insertion direction in the packing fitting groove (9) Since the interval between the side wall (9b) and the end face (2c) of the packing (2) facing the groove side wall (9b) differs according to the distance from the center of the joint body (1), the packing 2 is in the direction of arrow A. When it is pushed and moved, 2 is connected to the groove side wall 9b on the upstream side in the connecting pipe insertion direction of the packing fitting groove 9, so that the upstream end of the packing 2 in the connecting pipe insertion direction is By receiving the action of being pushed toward the groove bottom wall 9 a of the packing fitting groove 9, it is possible to effectively prevent the packing 2 from protruding from the packing fitting groove 9. Therefore, the sealing performance by the packing 2 can be ensured.

In the above embodiment, the end surface 2c on the upstream side in the connecting pipe insertion direction of the packing 2 is formed as the tapered surface 5 gradually narrowing toward the downstream side in the connecting pipe insertion direction, but the invention differs from the present invention. In this example, instead of this, as shown in FIG. 5, the taper surface 5 is gradually narrowed toward the downstream side in the connecting pipe insertion direction on the groove side wall 9b on the upstream side of the packing fitting groove 9 in the connecting pipe insertion direction. By doing so, it is possible to prevent the packing 2 from protruding from the packing fitting groove 9 at the time of gas leakage inspection or the like. Although not shown, in the embodiment of the present invention, the upstream end surface 2c of the packing 2 in the connecting pipe insertion direction and the groove side wall 9b on the upstream side of the packing fitting groove 9 in the connecting pipe insertion direction are both in the connecting pipe insertion direction. The distance between the groove sidewall on the upstream side in the connecting pipe insertion direction in the packing fitting groove and the end face of the packing facing the groove sidewall is from the center of the joint body. It may be different depending on the distance .

  The present invention is not limited to the joint body 1 that is integrally covered with the anticorrosion cylinder 6, and can be similarly applied to the joint body 1 that is not covered with the anticorrosion cylinder 6 as shown in FIGS. 6 and 7. The plug-in type pipe joint shown in FIG. 6 has the same packing 2 as that of the above embodiment in an annular packing fitting groove 9 provided on the inner periphery of the receiving port 7 opened at one end of the joint body 1 in the axial direction. However, a push ring 12 is screwed into a receiving port 11 opened at the other axial end of the joint body 1, and a packing 13 having a substantially triangular cross section fitted into the receiving port 11 by the push ring 12 is provided. It is meant to be retained.

It is a half notched cross-sectional view showing the plug-in type pipe joint of one embodiment of the present invention in a state where the connecting pipe is completely inserted. It is an expanded sectional view of the packing accommodating part in the plug-in type pipe joint of FIG. It is a partial cross section figure of the packing in the insertion type pipe joint of FIG. It is sectional drawing which shows the state which the packing of the packing accommodating part in the insertion-type pipe coupling of FIG. 1 moved to the upstream of the connection pipe insertion direction. It is sectional drawing which shows another Example corresponding to FIG. Furthermore, it is a half notch cross-sectional view which shows the plug-in type pipe joint of another Example in the state before connecting pipe insertion. FIG. 7 is a half-broken cross-sectional view showing the plug-in type pipe joint of FIG. 6 in a state where the connecting pipe is completely inserted. It is a half notched cross-sectional view showing the plug-in type pipe joint of the conventional example in the insertion completion state of the connecting pipe. It is an expanded sectional view of the packing accommodating part in the plug-in type pipe joint of FIG. It is a partial cross section figure of the packing in the insertion type pipe joint of FIG. It is sectional drawing which shows the state which the packing of the packing accommodating part in the insertion-type pipe coupling of FIG. 8 moved to the upstream of the connection pipe insertion direction.

P Connecting pipe 1 Joint body 2 Packing 2a Ring-shaped part 2b Lip part 2c End face 5 on the upstream side in the connecting pipe insertion direction 5 Tapered surface 7 Receptor 9 Packing fitting groove 9b Groove side wall on the upstream side in the connecting pipe insertion direction

Claims (1)

An annular packing fitting groove is provided in the inner periphery of the receiving port of the joint body having a receiving port into which the end of the connecting pipe is inserted, and the outer periphery of the end of the connecting tube and the receiving port are provided in the packing fitting groove. In the plug-in type pipe fitting that is fitted with a packing for sealing between the inner periphery of the packing fitting groove , the end face of the packing facing the groove side wall on the upstream side in the connecting pipe insertion direction in the packing fitting groove , It is formed in a tapered surface that gradually narrows toward the downstream side of the connecting pipe insertion direction,
The packing is a lip packing having a ring-shaped portion and a lip portion projecting radially inward from the inner periphery of the ring-shaped portion,
The gap between the groove side wall on the upstream side in the connecting pipe insertion direction in the packing fitting groove and the end surface of the packing facing the groove side wall is different according to the distance from the center of the joint body, Plug-in fittings.

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