DE1775103A1 - Connection piece - Google Patents

Description

Pafentanwälfe

DR.-ING. H. H. WILHELM

7000 Stuttgart-1 Stuttgart, April 4th

Gymnasiumstr. 31B T.I. 07 * 291133 Dr.W./pf

Re: Patent and utility model auxiliary application D 3484

Note: Wilhelm Keller KG.

7401 ΓΙ e h r e η District of Tübingen

Connection piece

The invention relates to a connector for connecting Pipelines with plastic parts, such as plastic housings 0. like

In order to connect metallic pipelines with plastic parts, for example with plastic valve housings, the connection pieces known for the connection of pipelines to metal parts have been used, ie connection pieces provided with a threaded pin have been screwed into the plastic parts. This type of connection has proven to be of little use in practice, since the mechanical hold of the connection piece made of metal in the plastic part is too low. This is due to the fact that the thread for the connecting piece weakens the plastic part too much, and because

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on the other hand, not even with Luderst careful assembly can be safely prevented that the thread is turned over in the plastic part. This risk of overturning the Thread in the plastic part is given in particular when the connecting piece itself with a further screw connection is equipped for fastening the pipeline. This risk is increased if the pipelines are made up of several fc individual pieces of pipe, which are in turn connected to each other by screw connections.

The invention is based on the object of avoiding these disadvantages and a connector of the type mentioned to create a good mechanical hold in the corresponding Has a plastic part and is not stressed by torsional loads. The invention consists in that the connector in a recess of the plastic part has plug-in, piston-like approach in the plastic part is immovable in the axial direction, but can be rotated. Since this connector only in the axial direction is held, the risk of overturning is avoided, since it evades all rotational loads.

An extremely advantageous embodiment of the invention is obtained if the kdben-like approach has an annular groove into which Engage pins that can be inserted into the plastic part. In order to achieve the lowest possible weakening of the plastic part,

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It is particularly advantageous if the pins are so oiniiteckbar in the plastic material that they can be de. ^iv i bottom of the liin ^ groove started tangentially.

The piston-like approach can be used to seal the connection piece advantageously with a further annular groove for receiving 3 one Sealing ringsG be provided and to the sealing ring not to be crushed during assembly, in an advantageous embodiment of the invention, the diameter of the piston artif gene approach and the plastic part be graded and the part of the approach with the smaller diameter can be the sealing ring wear. In order to be able to introduce the sealing ring well into the recess of the plastic part, it is finally particularly advantageous when the graduated diameter of the plastic part into one another via a conical connecting surface pass over.

In the drawing, the invention is shown in an embodiment g, for example. Show it:

Fig. 1 is a section through one with connection pieces according to the invention equipped plastic valve housing and

2 shows a section through the valve housing of the "Big. 1 antBprao'h" along the line II-II.

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-A-

The exemplary embodiment shows one way of connecting from! pipelines to a valve housing made of plastic 1. Leave with the connecting pieces 2 used there however, pipelines can easily be connected to other plastic parts or also via "specially designed" for this purpose Connect plastic parts together.

The connection pieces 2, which are provided with a screw connection 3 and are made of metal, are inserted into recesses of a plastic valve housing 1 which form a right angle to one another. The attachment of the connecting pieces 2 in the plastic housing 1 takes place via pins 4 inserted into the plastic housing, which engage in an annular groove 5 of the connecting pieces 2 in such a way that they lie tangentially on the base of the annular groove 5. This creates a very secure fastening in the axial direction of the connecting pieces 2, since these pins 4 have large contact surfaces in the plastic housing 1 and also in the annular groove. A particular advantage is that the w connecting pieces are rotatably mounted in the plastic housing 1 2, such that the screw 3 may be screwed to pipes themselves, without the plastic housing 1 is mechanically loaded by the screwing process. Either the screw connection 3 can be held and a union nut screwed onto the pipe end or, which is particularly advantageous for long pipe sections, the screw connection itself can be tightened in the manner of a screw and connected to the corresponding threaded end of the pipe section. Reactions of the aul ^ ebrcchtoi) torque it on the KunGtntofi rgliLuoe 1 do not occur.

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~ 5 -

In order to seal off the connection pieces 2 from the outside, they are provided with a further annular groove 6 into which a © ring "7 is used. In order to be able to introduce this O-ring 7 into the recess of the plastic housing 1 without closing it crush, the annular groove 6 is mounted on a part of the extension 8 of the connecting pieces 2 with a smaller diameter. The recesses of the plastic housing 1 are stepped accordingly, provided in a particularly advantageous manner is that the graduated diameter of the recess is about conical connecting surfaces 9 merge into one another, so that the O-rings 7 can be easily inserted during assembly.

In the embodiment shown serves in an advantageous manner one of the connecting pieces 2 at the same time as a valve seat for a movable via a handle 10 and a spindle 11 Valve body 12. Since the connecting pieces 2 are easily exchangeable by the way they are attached, the Screw connections 3 for the pipelines can also be designed with any thread diameter. This results in the particular manufacturing advantage that the plastic part 1 remains the same for all forms of connecting pieces can, if the piston-like lugs 8 of the connecting pieces 2 are formed in each case the same. This is especially so advantageous because the fittings made of metal can be changed relatively cheaply while for the change the plastic parts "each.veils expensive and complex tools are required üin: i.

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Claims (6)

-6- T775103 Patent and protection claims 1. Connection piece for connecting pipes with plastic parts, such as plastic housings o. The like. That is preferably itself is provided with a screw connection for a pipeline, characterized in that the connecting piece (2) one in a recess of the plastic part (l) has insertable, piston-like extension (8) which is immovable in the plastic part (l) in the axial direction, but is rotatably fastened. 2. Connection piece according to claim 1, characterized in that the piston-like projection (8) has an annular groove (5) into which in the plastic part (l) insertable pins (4) engage. 3. Connection piece according to claim 2, characterized in that the pins (4) can be inserted in such a way into the plastic part (l) are that they are tangential to the bottom of the annular groove (5). 4. Connection piece according to one or more of claims 1 to 3, characterized in that the piston-like projection (8) is provided with a further annular groove (6) for receiving a sealing ring (7). 10 9 818/1719 -T- 5 · connecting piece according to claim 4 »characterized in that because the diameter of the piston-like extension (8) and the recess of the plastic part (l) are graduated and the part of the extension (8) with the smaller diameter carries the sealing trough ring (7) ″. 6. Connection piece according to claim 5 »characterized in that the graduated diameter of the plastic part
(l) merge into one another via a conical connecting surface (9). 1098 18/1719 _Mm o «! G! NAl Blank page