JPH062791A - Slip-off preventing pipe coupling - Google Patents

Abstract

PURPOSE:To prevent the deflection of a lock ring in the insertion into an insertion port, as for a slip-off preventing pipe coupling in slip-on type. CONSTITUTION:A split lock ring 5 in the peripheral direction is installed in a lock ring accommodation groove 4 formed on the inner periphery of a receiving port 1. On the outer periphery at the top edge part of an insertion port 8, a projection part 9 which elastically spreads the diameter of the lock ring 5 and permits the passing in the lock ring 5, in the insertion into the insertion port 8, is formed. The projection part 9 is engaged with the lock ring 5 from the innermost side of the receiving port. An elastic holding ring 6 having a plurality of holding projection parts 7 for holding the outer peripheral surface of the lock ring 5 formed on the inner periphery is arranged between the inner peripheral surface of the lock ring accommodating groove 4 and the outer peripheral surface of the lock ring 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separation prevention pipe joint,
In particular, the present invention relates to a slip-on type separation prevention pipe joint in which the receiving opening and the insertion opening can be joined by inserting the insertion opening into the receiving opening.

[0002]

2. Description of the Related Art In a slip-on type pipe joint, a sealing material is attached to the inner periphery of a receiving port, and the receiving port can be joined to the receiving port by inserting the insertion port into the receiving port while compressing the sealing material. Is configured. As a slip-on type pipe joint provided with a separation prevention function, the applicant has conventionally proposed a separation prevention pipe joint having a configuration shown in FIG.

That is, in FIG. 5, an annular seal material 23 is arranged in the seal material accommodation groove 22 on the inner circumference of the receiving port 21, and a lock ring accommodation groove 24 is formed on the inner side of the seal material accommodation groove 22. The lock ring 25 is mounted in the lock ring receiving groove 24 in the circumferential direction. Between the outer peripheral side of the lock ring 25 and the inner peripheral side of the lock ring accommodating groove 24, a retaining rubber ring 26 for retaining the lock ring 25 is arranged. A protrusion 28 that can engage with the lock ring 25 from the rear side of the receiving port is formed on the outer periphery of the tip of the insertion port 27.

The retaining rubber ring 26 has an L-shaped cross section and is disposed so as to contact the inner peripheral surface and the rear side surface of the lock ring groove 24, and the lock ring 25 faces inward toward the opening side of the receiving port 21. Press on. Thereby, the lock ring receiving groove 24
The lock ring 24 engages with the tapered inner peripheral surface 24a formed on the receiving opening side. And lock ring 25
When the insertion port 27 is inserted, the projection 2 at the tip of the insertion port 27
The protrusion 28 is elastically expanded by 8 to allow the protrusion 28 to pass through the inside, and after the passage, the engagement with the protrusion 28 prevents the insertion port 27 from coming off the receiving port. It is possible.

[0005]

However, in such a conventional configuration, the lock ring 25 before insertion of the insertion port 27 is in a natural state of a small diameter and has a tapered inner peripheral surface 24a.
Since it is not always surely held by the holding rubber ring 26, there is a problem that it is likely to be eccentrically arranged and it may be difficult to insert the insertion opening 27.

Therefore, the present invention solves such problems and provides a disconnection prevention pipe joint which can prevent the eccentricity of the lock ring when inserting the insertion opening and can perform the joining work easily and surely. The purpose is to do.

[0007]

In order to achieve the above object, the present invention has a lock ring accommodating groove formed in the inner periphery of a receiving opening, in which a lock ring divided in the circumferential direction is mounted and inserted into the receiving opening. The lock ring is elastically expanded on the outer periphery of the tip of the insertion port when it is inserted so that the inside of this lock ring can pass to the inner side of the receiving port, and after passing, it is received by the lock ring. Form a protrusion that can engage from the back side,
An elastic holding ring having a plurality of holding projections for holding the outer circumferential surface of the lock ring formed on the inner circumference between the inner circumferential surface of the lock ring receiving groove and the outer circumferential surface of the lock ring. Is.

[0008]

According to this structure, when the elastic retaining ring is mounted on the inner peripheral surface of the lock ring accommodating groove and the lock ring is arranged on the inner peripheral surface of the groove, the lock ring is formed on the inner peripheral surface of the elastic retaining ring. It is held by the holding projection without eccentricity. For this reason, it is possible to prevent a problem due to such an eccentric state when the insertion opening is inserted. Also, when the projection at the tip of the insertion slot passes through the inner circumference of the lock ring, there is no hindrance because the retaining projection is easily elastically deformed. It returns to the reduced diameter state and fits on the outer circumference of the insertion slot, and the function of preventing separation is reliably exhibited.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 is a receiving port, in which a sealing material 3 is arranged in a sealing material housing groove 2 on the inner periphery thereof. A lock ring housing groove 4 is formed on the inner periphery of the receiving port 1 on the back side of the sealing material housing groove 2, and the lock ring 5 is housed in the lock ring housing groove 4 in the circumferential direction. An elastic holding ring 6 made of rubber is interposed between the outer peripheral surface of the lock ring 5 and the inner peripheral surface of the lock ring housing groove 4.
A plurality of holding protrusions 7 are formed on the inner circumference of the elastic holding ring 6 at appropriate intervals in the circumferential direction. The holding protrusion 7 is configured to have a triangular cross-sectional shape. Reference numeral 8 denotes an insertion opening inserted into the receiving opening 1, and a protrusion 9 that can engage with the lock ring 5 from the rear side of the receiving opening is formed on the outer periphery of the tip end thereof.

Lock ring receiving groove 4 on the receiving opening side
A taper surface 14 is formed on the inner circumference of the lock ring 5, and when the lock ring 5 moves toward the opening side of the receiving port 1, the outer peripheral edge of the lock ring 5 engages with the taper surface 14. Therefore, the lock ring 5 is pressed against the outer peripheral surface of the insertion slot 8 by the withdrawal force of the insertion slot 8, and the engagement between the lock ring 5 and the protrusion 9 is ensured, and highly reliable removal prevention Function is secured.

A taper surface 15 is formed on the inner circumference of the receiving opening side portion of the lock ring 5, and a taper surface 18 is formed on the outer circumference of the tip end portion of the insertion opening 8.
The diameter of the lock ring 5 is smoothly expanded at the tip of the lock ring 5, and the insertion opening 8 can be inserted into the lock ring 5.

At the time of joining the receiving opening 1 and the insertion opening 8, the sealing material 3 is housed in the sealing material housing groove 2 of the receiving opening 1. Further, the elastic holding ring 6 is mounted in the lock ring housing groove 4, and the lock ring 5 is arranged on the inner circumference thereof. Then lock ring 5
Are held by the holding projections 7 formed on the inner circumference of the elastic holding ring 6 without being eccentric to the axial center of the receiving port 1.

In this state, the insertion opening 8 is inserted into the receiving opening 1. Then, first, the sealing material 3 is compressed on the outer periphery of the insertion opening 8 to secure the seal between the receiving opening 1 and the insertion opening 8. Further, since the lock ring 5 is held by the elastic holding ring 6 without being eccentric, it is possible to prevent a problem that the tip of the insertion opening 8 is caught by the lock ring 5 and cannot be smoothly inserted. Then, as shown in FIG. 3A, when the insertion opening 8 is pushed in with the tip of the insertion opening 8 engaged with the inner circumference of the lock ring 5, the taper surface 18 on the outer circumference of the tip of the insertion opening 8 is locked. Tapered surface 1 on the inner circumference of ring 5
The lock ring 5 elastically expands in diameter by the interaction with 5, and the projection 9 on the outer periphery of the insertion slot 8 easily passes through the inner periphery of the lock ring 5 as shown in FIGS. To do.

Here, when the projection 9 passes through the lock ring 5, the elastic holding ring 6 is compressed as shown in FIG. 3B, but since the holding projection 7 is mainly compressed, the compression thereof is performed. Can be performed relatively easily, and the insertion of the insertion opening 8 can be performed easily without causing a great resistance.

After the protrusion 9 has passed the lock ring 5,
The lock ring 5 returns to the original state and fits securely on the outer periphery of the insertion slot 5. Therefore, the engagement between the lock ring 5 and the protrusion 9 provides a reliable function of preventing separation.

The cross-sectional shape of the holding projection 7 of the elastic holding ring 6 is not limited to the above-mentioned triangle, but may be a rectangular shape as shown in FIG. 4, for example. A shape can also be adopted.

[0017]

As described above, according to the present invention, since the lock ring is held without eccentricity by the retaining projection on the inner circumference of the elastic retaining ring, the eccentricity is achieved when the insertion opening is inserted into the receiving opening. Not only can the inconvenience due to the state be prevented, but when the projection at the tip of the insertion slot passes through the inner circumference of the lock ring, elastic deformation of the holding projection makes the lock ring easily elastic. The diameter can be increased.

[Brief description of drawings]

FIG. 1 is a sectional view of a separation prevention pipe joint according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the lock ring in FIG. 1 and an elastic retaining ring around the lock ring.

FIG. 3 is a cross-sectional view of essential parts showing a step of joining the receiving opening and the insertion opening shown in FIG.

FIG. 4 is a view showing an elastic retaining ring according to another embodiment of the present invention.

FIG. 5 is a sectional view of a conventional separation prevention pipe joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receptacle 4 Lock ring accommodating groove 5 Lock ring 6 Elastic holding ring 7 Retaining projection 8 Inserting slot 9 Projection

Claims (1)

[Claims] 1. A lock ring accommodating groove formed in the inner periphery of the receiving opening is fitted with a lock ring divided in the circumferential direction, and the lock ring is inserted into the outer periphery of the tip of the insertion opening inserted into the receiving opening. The lock ring is elastically expanded in diameter so that it can pass through the inside of this lock ring to the rear side of the receiving port, and after passing through, the lock ring is formed with a protrusion capable of engaging from the rear side of the receiving port, Between the inner peripheral surface of the lock ring receiving groove and the outer peripheral surface of the lock ring, an elastic retaining ring having a plurality of retaining protrusions for retaining the outer peripheral surface of the lock ring is formed on the inner periphery. Disengagement prevention pipe fittings.