Nipple for a hermetical coupling between pipes

Abstract: This nipple is of the type comprising at least one of the necks wherein the associated pipe (T), an annular sealing gasket (2) retained between an inside step (3) of said neck (1) and a bushing (4) inserted into the neck will be engaged and this nipple having at the opposite end in contact with said gasket (2) a rim (5) applied against the mouth of the neck (1) and characterized in that said bushing (14) has an external peripheral undercutting (12) between said rim (5) and the edge of the opposite end, whereby a small rim (13) is being configured in said edge and any accidental exit of the bushing (4) from the neck (1) is prevented,if disengaged for any reason whatever the pipe (T) clamping members,being then in abutment said rim (13) with an inside peripheral rib (14) of the neck (1) and avoiding therefore to the user unaware of the nipple construction all the problems derived when reassembling the nipple.

Description: The present invention relates to a nipple for a hermetical coupling between pipes according to the preamble of claim 1. This nipple is of the type comprising two or more coupling necks and at least one of the necks having inside an annular sealing gasket retained between a neck step and a bushing inserted thereinto and bearing on the neck mouth by means of an external rim having said bushing at the opposite end to the end contacting the gasket. The pipe to be connected to this neck remains closely fitted when inserted thereinto by means of said gasket and the clamping to the neck is obtained with a nut engaged on said neck and operating, if suitably handled, on a tapered external surfaced gripping-clamp being seized over said pipe. A drawback is seen however in this type of known nipples in that if the nut is disengaged for any reason whatever, not only then goes off also the gripping-clamp, but also the bushing can accidentally go off and even the gasket too, raising for the user not aware of the nipple construction the subsequent problem of having to suitably reassembly the nipple placing each part at the respective location. Another drawback is seen in these nipples in that a hermetical gasket at times has a seemingly poorly formed construction preventing it to be correctly close-fitted to the associated pipe bringing about then a defective sealing in the pipe coupling. These drawbacks or problems and other derived therefrom can be remedied with the nipple being the object of the present invention having as a main characteristic the fact that said bushing has an external peripheral undercutting between the rim engaged against the mouth of the neck and the edge of the end contacting the gasket, in this edge being configured a small rim which if the bushing is outwardly displaced because of said disengagement of the pipe clamping members, this small rim abuts against the peripheral rib provided inside said neck to prevent any accidental exit of the bushing and possibly also of the gasket, the user being thus avoided the problem of reassembling the nipple. Advantageously, the bushing portion inserted into the neck has a length somewhat greater than that existing between the gasket, when it is placed against the inside step of said neck, and the mouth of the neck, so that if the nut is tightened against the gripping-clamp to have the latter seized well on the pipe, the gripping-clamp is then longitudinally moved driving the bushing applied against the sealing gasket, which is axially compressed and radially expanded against the pipe without any possibility of creating voids or any slits capable of obstructing the sealing sought for in the coupling. To facilitate further the explanation, the present description is accompanied by a drawing sheet showing a practical:case of embodiment only cited by way of a non-exhaustive example of the scope of the present invention. In the drawings: Figure 1 is a half-sectioned side view of the nipple portion associated to a neck and a pipe being already connected thereto, and Figure 2 is a perspective view of said neck with the bushing ready to be fitted thereto but without the pipe clamping members to be connected which are not either illustrated. According to these figures, the nipple for a hermetical coupling between pipes as illustrated comprises a body (not shown) possibly having several configurations in accordance with the number of connecting necks involved and the nipple requirements, these necks comprising or at least one of them, neck 1, an annular O-ring 2 closely fitted inside said neck 1, the O-ring remaining retained between an inside step 3 thereof and a bushing 4 inserted into said neck. Bushing 4 having at the opposite end to the one end contacting said gasket 2, a L-shaped peripheral rim 5 wherein is inserted the wider end of an outwardly tapered gripping-clamp 6, so that a nut 7 may be tightened thereover, this nut threadedly engaged on the neck 1 and forced to sink into the pipe T inserted into said neck by means of inside peripheral teeth means 8 provided on said gripping-clamp, whereby after the nut is strung together with the gripping-clamp 6, the bushing 6 and the O-ring 2, the nut abuts then against a step 9 inside the neck 1, remaining thus the neck ready for said clamping. Nut 7 having at the frontal portion 7', the one where it is threadedly engaged on the cylindrically configured neck 1, external longitudinal rib means 10 equally spaced and distributed to facilitate handling while the rear portion 7'' is narrower and tapered to suitably operate on the gripping-clamp 6. Moreover, bushing 4 having in the portion inserted into the neck 1, a somewhat greater length than the inside portion of said neck going from the mouth of the neck to the O-ring 2 and consequently a small space 11 remained between the rim 5 of said bushing 4 and the mouth of the neck 1 at the passive portion of the nut 7 which if operated on the gripping-clamp 6 longitudinally displaces the latter and the bushing 4 is then also driven by the gripping-clamp 6 against the gasket 2 which on being axially compressed is radially expanded against the neck 1 and the pipe T,the coupling hermetical sealing is thus firmly secured. Bushing 4 having also an external peripheral undercutting 12 between rim 5 and edge of the opposite end contacting with the gasket 2 remaining configured in this edge a small rim 13 which, if the nipple-nut 7 is disengaged for any reason whatever, with the nut will only go out the gripping-clamp 6 because the rim 13 of the bushing 4 will be abutting with an inside peripheral rib 14 of said neck 1 if said bushing is outwardly slided from the neck 1,preventing the neck any accidental exit of said bushing 4 and the subsequent coupling of said gripping-clamp 6 and nut 7 will thus be facilitated.

Claims: Nipple for a hermetical coupling between pipes comprising at least one of the coupling necks (1) of one of the pipes, an annular sealing gasket (2) retained between an inside step (3) of said neck (1) and the end of a bushing (4) inserted thereinto and the other end having an external rim (5) applied against the mouth of said neck (1), characterized in that said bushing (4) has an external peripheral undercutting (12) between said rim (5) and the edge of the opposite end thereof in contact with the gasket, in this edge being configured a small rim (13) such that, in case the bushing becomes outwardly displaced from the neck because the clamping members are disengaged from the associated pipe, this rim (13) will then be in abutment against a small rib (14) provided at the inside periphery of said neck (1) which will prevent thereby any accidental exit of the bushing (4) and even of the gasket (2). Nipple for a hermetical coupling between pipes, according to claim 1, wherein the bushing portion inserted into the neck (1) has a somewhat greater length than that existing between the gasket (2) and the mouth of said neck (1), such that if the nut (7) engaged on the neck (1) is tightened and a gripping-clamp (6) whereto the associated pipe (T) is seized thereon is operated thereupon by the nut (7), the gripping-clamp (6) will then be longitudinally displaced and the bushing (4) driven against the gasket (2) which on being axially compressed will also be radially expanded against said pipe (T) already closely fitted by the gasket (2) and the coupling sealing will thus be firmly secured.

Inventors: PLANES VILA JUAN C O FORPLAST, PLANES VILA, JUAN, C/O FORPLAST, S.A.
Applicants: FORPLAST SA, FORPLAST, S.A.
Application year: 1993
Main classification: F16L19
IPC codes: F16L19, F16L47