Such connectors are usually employed to connect portions of pipes of various kinds and may be differently shaped according to their use.

Background Art Currently produced connectors comprise fastening means of various types such as, for instance, threads provided on the connectors themselves, flanges fitted with seats to house bolts and the like, etc.

On such connectors is provided a seat extending over a full circumference obtained on the head surface of the connector itself and positioned coaxially to its inner cavity, seat which is destined to house an annular gasket called O-Ring. In the remainder of the description the terms O-Ring and gasket shall be used interchangeably.

Upon mounting prior art connectors, housing and maintaining the gasket in the appropriate seat constitute a drawback.

This is because it is necessary to mount the gasket in the seat at the time of use and, moreover, it is necessary to hold the gasket itself until final assembly of the connected parts.

Maintaining the O-Ring in the seat may be relatively simple in those cases in which the portion of the connector involved in the coupling faces upward but, when it faces downward, or it is vertical, it becomes necessary to use auxiliary substances such as grease or adhesives to maintain the O-Ring in its seat during assembly operations. The latter operating situation is more difficult in those cases in which the

operator works "in the dark", i.e. has no direct vision of the parts to be connected.

Moreover, under particular environmental conditions, the grease tends to melt, thus not assuring the proper positioning of the gasket in the seat.

In practice, there are problems related to the time required to position the 0- Ring in the seat and to the need to store the gaskets and the auxiliary substances.

Moreover, the success of the operation is closely connected to the experience and skill of the operator.

Disclosure of the Invention The object of the present invention therefore is to eliminate the drawbacks mentioned above with a connector for fluid passage systems wherein the housing seat for the O-Ring is shaped in such a way as to hold the O-Ring itself stably within it.

With the subject connector it is not necessary to insert the gasket on the connector at the moment the connector is fitted in place, but the association between O-Ring and connector may be performed beforehand. Thus, not only is the operation simplified, but the presence of additional containers for the gaskets and the auxiliary fastening substances is eliminated as well.

Integrating the gasket with the connector body eliminates the need for specific orders or dedicated warehouse positions.

As no specific skills are required for mounting, the operation is essentially safe and not affected by the operator's level of professional expertise.

The technical characteristics of the invention, according to the aforesaid purposes, can clearly be seen from the content of the claims reported below and its advantages shall be made more evident in the detailed description that follows, made with reference to the attached drawings, which show an embodiment provided purely by way of non limiting example, wherein: - Figures 1, 3, 5, 7, 9 show, in side view with some parts sectioned off the better to show others and an enlarged detail in Figures 1, 3 and 7, some possible embodiments of connectors in accordance with the present invention; - Figures 2, 4, 6, 8, 10 show, in respective side views with some parts sectioned

off the better to show others, examples of prior art connectors for hydraulic and pneumatic systems, similar respectively to the examples as per Figures 1, 3, 5, 7 and 9.

In accordance with the figures of the attached drawings, a connector for hydraulic and pneumatic systems can be used to connect pipes or other parts of systems together. The connector is indicated with the number 1 when an example pertaining to the object of the present patent application is shown, as in Figures 1, 3, 5, 7 and 9; when instead the figure pertains to a prior art connector, the connector is indicated with 1' Pipes and other system parts are not shown in the attached drawings since they are not the object of the present invention.

For the connection, the connector is provided with suitable fastening means which may be constructed differently according to the use.

For instance, as in the examples shown in Figures 1, and 2, the fastening means may be constituted by the threading 5 presented by the connector itself.

Alternatively, screw or bolt means 6 may be provided, to be used in combination with flanges or semi-flanges; examples of this kind are shown in the Figures from 4 to 10.

The connector presents a hole 4 for the passage of a fluid (which in hydraulic systems will be hydraulic fluid) and a seat with circular development positioned coaxially with respect to the hole 4 of the connector.

The seat is indicated with 2' in the examples pertaining to prior art connectors and with 2 in those pertaining to the invention.

The seat 2 or 2' is obtained on the head surface 7 and it is destined to house an annular gasket 3 or O-Ring.

The seat 2 or 2', viewed according to a section coplanar to the axis X of the hole 4, has the shape of an open quadrilateral, with a base portion or base 20 or 20' essentially perpendicular to the axis X of the hole 4 and two walls 21, 22 or 21', 22' defined by rotational surfaces.

In the examples of the prior art, as shown in Figures 2, 4, 6, 8 and 10, the seat

presents a quadrilateral section with the side walls 21' and 22' defined by cylindrical surfaces which, in section, are essentially perpendicular with respect to the base 20': with a seat so shaped the O-Ring 3 positioned in the seat itself cannot be held, leading to the drawbacks mentioned in the previous part of the description.

In the examples pertaining to the present invention at least one of the walls 21, 22 is tilted with respect to the base 20, i.e. not perpendicular thereto so as to define a tooth 23 delimiting the seat 2 thus holding gasket 3 stably inserted.

In particular, both walls 21 and 22 are tilted with respect to the base 20 and parallel to each other so as to define, in section, a parallelogram tilted inward, i.e.

towards the axis X of the hole 4.

As can be seen more clearly in the enlarged detail shown in Figure 1, the walls 21 and 22 can be tilted, with respect to the perpendicular with the base 20, by an angle a approximating 300. In detail, the wall 21 defines with the axis X, externally to the head surface 7, an angle a, whereas the wall 22 defines an angle a': in the example shown these angles are equal and approximate 300.

In other words, in the parallelogram defined in section, the angle P between base 20 and wall 21 approximates 60°, whereas the angle y between base 20 and wall 22 approximates 1200.

The invention thus conceived can be subject to numerous modifications and variations, without thereby departing from the scope of the inventive concept.

Moreover, all components may be replaced with technically equivalent elements.