MXPA98004521A - Grommet cup packing made of elastomeric material for hydraulic apparatus - Google Patents

Abstract

A seal packing made of elastomeric material (9) for a hydraulic apparatus adapted to be inserted in a seat (3) that is recessed into one of two parts (1, 4) between which a seal is to be established and to be pushed elastically into contact with the other part. The packing has a composite structure which is comprised of an elastomeric material (9) in the portions intended to establish the seal and of a rigid or semirigid core (11, 12) material that is at least partly incorporated into the elastomeric material of the packing.

Description

INTERNAL RING CUP PACKAGING MANUFACTURED OF ELASTOMERIC MATERIAL FOR HYDRAULIC APPARATUS TECHNICAL FIELD This invention relates to an inner ring cup packing made of elastomeric material for hydraulic apparatus.

BACKGROUND OF THE INVENTION These gaskets are used to form a seal between two cooperating parts of a hydraulic apparatus, mainly taps (valves or valves) and cartridges for taps. The cup packing is inserted into a seat that is housed in one of the two parts between which a seal must be established and is forced to contact the other party. The force is often applied by a spring housed inside the cup package, but it can also be applied by means of various elements or variously arranged elements or by the elasticity of the elastomeric material comprising the cup packing. To establish the best possible hydraulic seal, these gaskets must be made of an elastomeric material that has a high degree of elastic yield. As a rule, conventional cup packages have a circular cross section. REF: 27611 Conventional and known cup packages have serious disadvantages. For technical and regulatory reasons, the hydraulic apparatus must have the capacity to withstand high pressures, which according to some standards, reach 50 bars and even 120 bars. If the cup packages consist of elastomeric material under high pressures and especially in the case of pressure variations, they can deform and may even burst. This means that such packages must be manufactured with a relatively rigid elastomeric material, which is unable to establish the best possible seal. This phenomenon is also present when the packages are installed under operationally static conditions. When such packages are used under operationally dynamic conditions, that is, when they must establish a seal between movable parts alternatively, there is still another disadvantage. When one of the two parts, between which the cup packing establishes a seal, is displaced with respect to the other part in which the cup packing sits, then the packing tends to be dragged, due to friction and so. If the moving part is a shutter having holes or openings which must be opened or closed during the displacement, then the deformation of the packing modifies the relative positions in which the openings or through holes are controlled and if the deformation is excessive, deteriorates the accuracy of the shutter operation and may even alter the proper closure, for example of a tap or valve (valve). It has been proposed to stiffen or reinforce a cup packing by inserting a cap made of rigid material such as plastic. However, this method has not proved to be sufficiently effective due to the fact that the pressure can be transmitted to the interface between the cup pack and the inserted bushing and can thus act on the package itself to cause the disadvantages discussed above. A purpose of this invention is to provide a cup packing consisting of a relatively elastic elastomeric material, which would have the ability to establish a good seal and which would be able to withstand high pressures and pressure variations. Another purpose of this invention is to provide a cup packing which would be particularly suitable for dynamic operation, due to the fact that it does not undergo excessive deformation due to friction by displacement of the parts between which the seal is established.

Still another object of the invention is to provide a cup pack which can be formed with a non-circular cross section.

BRIEF DESCRIPTION OF THE INVENTION These objects are obtained according to this invention in virtue of the fact that the package has a composite structure. This composite structure comprises an elastomeric material (which may have considerable yield or flexibility) in the portions designed to establish a seal and a rigid or semi-rigid material (such as a plastic material or an appropriate metallic material) corresponding to a core which is incorporated at least partially into the elastomeric material of the package. In this composite structure, the elastomeric material only works to establish the hydraulic seal. It is thus virtually relieved of all the mechanical strength functions of the packaging which are carried out completely or almost completely by the built-in core, which takes the stresses to which the packaging is subjected, under static conditions and under dynamic conditions . This means that it can be designed separately with different criteria, especially with respect to the choice of materials, the two parts of the packaging structure. The packing of the present invention has a high degree of sealing due to the choice of a sufficiently yielding or elastic elastomer and a high degree of resistance to deformations due to the choice of appropriate shapes and composition of the core. Preferably, the core which is incorporated in the elastomeric material is provided with securing means that can secure the elastomeric material to the core itself. In particular, the core may consist of an axially extending portion, having a cross-section substantially corresponding to the cross-section of the packing, from which the flange sections extending at least partially extend laterally, so as to extend laterally. radial in the elastomeric material. The packing of this invention is preferably manufactured by injecting an elastomeric material in a fluid state into a mold, to incorporate a rigid or semi-rigid core and then the cross-linking of the elastomeric material constituting the package. In contrast to conventional and known cup packages, the package of this invention need not have a circular cross-section. The package can diverge considerably from this usual circular shape, provided that the seat on which it sits has a corresponding shape. It is also possible to provide different forms to the portion of the package that sits on a seat of one of the two parts between which the seal is established and to the portion of the package that provides the seal. These and other features, purposes and advantages of this invention will become apparent from the following description of some of the embodiments illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 schematically illustrates in axial cross section, how a prior art and conventional packaging is deformed by high internal pressure. Figure 2 illustrates an embodiment, in axial cross section, of a package of the present invention; Y Figure 3 illustrates a second embodiment, in axial cross section, of the package of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Conventional packaging and prior art, illustrated in Figure 1, is designed to establish a seal between a first part 1 (e.g., the bottom of a tap or a cartridge for a tap (key or valve)) and a second part 4 (for example, a fixed flow control plate) having respective passages or passages 2 and 5 therein. The first part has a recessed or recessed seat 3 in which the package is inserted. The conventional packaging and the prior art comprises a body 6 made of elastomeric material provided with external peripheral projections to provide a seal on the seat 3 of the first part 1. The body 6 at its upper end forms a head 7 which forms a seal with the lower surface of the second part 4. A spring 8 is disposed in the body 6 of the package and works between the bottom of the seat 3 and the head 7 of the package, to urge the head 7 to contact the second part 4, at an effective pressure to establish a seal. When a high pressure is transmitted to the interior of the body 6 through the passages 2 and 5, the head 7 of the package tends to be pushed outwards, in the space separating the two parts 1 and 4 and is deformed, as shown in Figure 7A on the left side of Figure 1. This deformation may be permanent and may alter the operation of the package. This leads to the aforementioned disadvantages, which the present invention seeks to prevent.

Figures 2 and 3 show two embodiments of the cup packaging of the present invention. In these two figures, the parts corresponding to those in the figure 1 are named with the same reference numbers and will not be described further. The packing of the modality illustrated in the figure 2 comprises a body 9 made of elastomeric material with peripheral projections for the seal in the seat 3 of the first part 1 and a head 10 adapted to provide a seal against the lower surface of the second part 4. In the body 9 and the head 10 a center or core made of rigid material consisting of a portion 11 extending axially along the body 9 with a cross-section substantially corresponding to that of the cup packing and upper flange sections is at least partially incorporated. which extend into the interior of the head 10. The presence of this core prevents the deformation of the body, specifically of the head 10 in the presence of high pressures that are transmitted through passages 2 and 5 to the interior of the body 9. An appropriate selection The shape of the core 11, 12 and the material that it comprises will allow the pressure resistance of the package to reach any value that could be required for regulatory or technical reasons.

Preferably, as shown in Figure 2, the portion 11 of the core extends downward to form sections of the flange 13 that hold the bottom of the body 9 made of elastomeric material, to thereby contribute to its stability. In the embodiment illustrated in Figure 3, the center portion 11 has its upper flange sections 12 incorporated in the head 10 of the package, which, as shown, are rotated outwardly instead of inwardly as in FIG. embodiment of figure 2. The ridges can also be provided on both sides of the portion 11, that is, in front or extending inwards and outwards. This arrangement is shown in Figure 3 by the flange section 14, which is arranged to correspond to the lower surface of the head 10 and which serves the functions of providing a rigid support surface for the spring 8. It will be understood that the flanges 13, as illustrated in Figure 2, and the flanges 14, as illustrated in Figure 3, could be found in the same structure. The flange sections 12, 13 and 14 can extend continuously around the core portion 11 to give the latter greater resistance to radial stresses. As an alternative, the flange sections can also be interrupted or perforated to ensure a more perfect securing of the core with respect to the elastomeric material. For the same purpose, portion 11 may also have perforations. The cup packing is preferably prepared by injecting an elastomeric material in the fluid state to form the body 9 and the head 10 to a mold containing a center or core 11 and flanges 12, 13, 14 comprising a rigid material or semirigid and crosslinking of the elastomeric material comprising the package. This procedure constitutes a convenient and easy process of manufacturing the composite packages. The procedure is facilitated if (as in the modes shown) the incorporated core remains partially uncovered towards the outside. This makes it possible to provide in the mold effective supports for the core to be incorporated in the elastomeric material. In the embodiments illustrated in Figures 2 and 3, the package is moved in engagement with the part 4 by a spring 8 housed in the body 9. However, the spring 9 can be arranged in a different manner or can be replaced by any other elastic medium. In particular, the lower portion of the body 9 can extend beyond the end of the core 11 and be arranged in this manner to lean against the bottom of the seat 3 and to provide the elastic thrust required by the packing.

In view of the great strength that can be imparted to the cup package of the present invention, the package is not limited to a circular cross-section and may be different from the shape that is inserted into a corresponding seat 3. In particular, the head 10 of the package can have a shape that is different from that of the body 9. While the invention has been described in combination with specific embodiments thereof, it is clear that many alternatives, modifications and variations can be made by those experienced in the art in light of the foregoing description. Thus, it is proposed to cover all such alternatives, modifications and variations insofar as they fall within the spirit and broad scope of the appended claims. It is noted that, in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it refers. Having described the invention as above, property is claimed as contained in the following

Claims (11)

1. Claims 1. An inner ring cup package comprising elastomeric material for a hydraulic apparatus adapted to be inserted into a seat housed in a two-part between which a seal is to be established, the package is characterized in that it comprises a composite structure comprising an elastomeric material in the portions adapted to establish a seal and a rigid or semi-rigid material comprising a center or core that is at least partially incorporated in the elastomeric material of the package.
2. 2. The package according to claim 1, characterized in that the elastomeric material exhibits a considerable yield.
3. 3. The packaging in accordance with the claim 1, characterized in that the material comprising the core is a plastic material or a metallic material.
4. The package according to claim 1, characterized in that the core that is incorporated in the elastomeric material is provided with securing means that secure the elastomeric material to the core.
5. The package according to claim 4, characterized in that the nucieo comprises an axially extending portion having a cross section substantially corresponding to that of the packing and from which the flange sections project substantially laterally.
6. The package according to claim 5, characterized in that the flange sections extend in a continuous manner around the portion of the axially extending core.
7. The package according to claim 5, characterized in that the flange sections are perforated.
8. 8. The packaging in accordance with the claim 5, characterized in that the portion of the axially extending core has perforations.
9. The package according to claim 5, characterized in that it is manufactured by injecting an elastomeric material in a fluid state into a mold to incorporate a rigid or semi-rigid core and successively proceeding to the crosslinking of the elastomeric material.
10. 10. The package according to claim 1, characterized in that it has a non-circular cross section. The package according to claim 1, characterized in that the portion of the package adapted to be inserted into a seat of one of two parts between which the seal is going to be established has a shape different from that of the portion of the package that form the seal.