JP3369072B2 - Detachment prevention ring - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a separation prevention ring mounted on a separation prevention type connecting ring. 2. Description of the Related Art A pipe joint at a portion of a pipeline where an axial tensile force or an internal pressure acts needs to be provided with a preventive measure to prevent the outlet from being pulled out. For example, a thrust axial force is generated at a bent portion of a pipe by a water flow flowing inside the pipe, and this is a force for moving the pipe to the outside of the bent portion. . [0004] In some cases, a strong axial external force acts due to an earthquake or the like. Therefore, at the bent portion of the pipeline, the pipe is fixed with a concrete foundation or the like so as to oppose the external force as described above, so that the pull-out force does not reach the adjacent pipe joint. However, it is difficult to construct the above-mentioned concrete structure at a bent portion of a pipeline in an urban area where buried objects are congested, and it is necessary to provide a pipe joint adjacent to the bent portion with a detachment preventing function. Required. In order to achieve such an object, there has been known a detachable connecting ring as shown in FIG. The above-mentioned separation-prevention type connecting ring has a plurality of projections C... C provided in the inside of both receiving pipes A formed of ductile cast iron pipe or the like, in which a separation prevention ring B is inserted and provided on the inner surface circumferential direction of the separation prevention ring B.
In order to prevent disengagement by engaging a projection E at the insertion end of the pipe insertion D, the engagement between the projection C and the projection E at the insertion tip against a normal pulling force due to a thrust axial force or the like. When a strong axial external force is applied due to an earthquake or the like, as shown in FIG. This is prevented from being generated in the mouth tube A, and then prevented from coming off by the next projection C, and finally can be prevented from being pulled out by the lock ring F fitted into the inner surface of the receiving port. [0007] However, in the above, the separation prevention ring B is usually made of plastic, so that its material strength is low, and there is a drawback that it may not be possible to exert sufficient resistance to prevent it from coming off. . Further, in the case of a plastic detachment prevention ring, there is a concern that the heat-proof strength is low, and there is a problem of deterioration over time. Furthermore, since a plastic release ring requires a molding device such as an injection mold for molding, the production cost is not required when there is a large demand, but when the release prevention ring is used for a special pipe joint with a small demand. However, there is also a problem that it is bulky and very expensive. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to provide an inexpensive ring which is strong in strength, does not deteriorate over time, and can be manufactured at low cost. Things. That is, the detachment prevention ring according to the present invention comprises a ring-shaped thin metal plate joined to a ring main body which is curved and formed into a cylindrical shape by joining but not joining both ends of the thin metal plate.
The insertion protrusion is caught by the insertion protrusion formed at the insertion end and the insertion exit
In order to prevent breakage, the U-shaped tongues are bent in the inner diameter direction at appropriate intervals in the circumferential direction along the folding line in the circumferential direction, and a plurality of rows of the circumferential tongues are provided in the axial direction. It is characterized by becoming. Next, an embodiment of the present invention will be described. FIG. 1 is a front view showing an embodiment of a separation prevention ring according to the present invention, FIG. 2 is an end view taken along the line YY of FIG. 1, and FIG. 3 is an enlarged sectional view of the tip of a U-shaped tongue. is there. As shown in FIG. 4, a detachment prevention ring 1 of the present invention is formed on a ring-shaped main body 3 which is formed into a tubular shape by joining both ends 2 and 2 of a strip-shaped thin metal plate without joining them .
It is caught by the insertion projection 8 formed at the end of the insertion
The U-shaped tongues 5... 5 are bent in the radial direction at appropriate intervals in the circumferential direction so that the broken line 4 extends along the circumferential direction so as to prevent the tongues from slipping out. A plurality of rows are provided in the direction. In the above, the tip 5A of the U-shaped tongue 5
As shown in FIG. 3, the cross-sectional shape is a knife edge end surface in addition to a right angle end surface. The detachment prevention ring 1 is formed by engraving a U-shaped tongue piece on a strip-shaped thin metal plate by a roll press, cutting the tongue piece at a predetermined length, bending the tongue piece 5 and bending it into a cylindrical shape. You. The ring 1 is used by being arranged on the inner surface of the receptacle 6 as shown in FIG. At this time, since the separation prevention ring 1 has a C-shaped cross section in the radial direction, the circumferential length is smaller than the inner diameter of the receiving port 6 and the ring body 3 has a large gap between the butted ends. 6, it is elastically fitted into the housing 6 and mounting becomes very easy. When the insertion port 7 is inserted, the locking projection 8 formed at the end of the insertion port is caught on the U-shaped tongue piece 5, and the insertion port 7 is prevented from being detached from the receiving port 6. . In the figure, 9 is a lock ring, 9A is a rubber seat for centering the lock ring, 10 is a rubber ring, 11 is a press ring, 12 is a flange,
Reference numeral 13 denotes a push ring mounting bolt. According to the present invention, since the detachment prevention ring is formed of a thin metal plate as described above, it has strength as compared with synthetic resin, and has the effect of reducing the thickness while securing the required strength. Have. Further, since it is made of metal, it has excellent heat resistance and does not have the problem of aging. In addition, there is an effect that continuous production can be performed by a roll press or the like, and mass production can be performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing an embodiment of a separation prevention ring. FIG. 2 is an end view taken along line YY of FIG. 1; FIG. 3 is an enlarged view of a tip portion of a U-shaped piece. FIG. 4 is a cross-sectional view showing an embodiment. FIG. 5 is an explanatory sectional view of a conventional example. FIG. 6 is an operation explanatory sectional view of a conventional example. [Description of Signs] 1 ... Separation prevention ring 2 ... Both ends of strip-shaped thin metal plate 3 ... Ring body 4 ... Folded line 5 ... U-shaped tongue 5A ... Tip 50 of U-shaped tongue 50 ... Circumferential tongue Row 6: Receiving port 7: Insertion port 8: Locking projection

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-10-185037 (JP, A) JP-A-9-189385 (JP, A) JP-A 10-238672 (JP, A) 132292 (JP, U) JP-A 4-122890 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16L 21/00-21/08

Claims (1)

(57) [Claims 1] An insertion hole is formed in a ring-shaped ring main body which is formed by joining but not joining both ends of a strip-shaped thin metal plate.
Get caught by the insertion projection formed at the end
In order to prevent this, the U-shaped tongues are bent in the inner diameter direction at appropriate intervals in the circumferential direction along the circumferential lines, and a plurality of circumferential tongue rows are provided in the axial direction. A separation prevention ring characterized by the following.