EP0734709A2 - Access port for a bag made of soft synthetic material - Google Patents

Abstract

The access spout has a collar (4) at one end of an access tube (2) with a thin wall which can be perforated and placed inside the tube and separating the interior of the tube into two sealed zones. The tube wall has an area of reduced thickness between the perforable wall and the second end of the tube and the latter is closed by a weld. The access tube can be formed in one piece. The collar can be folded into a V-section with a rounded base.

Description

The present invention relates to a device for accessing a pocket made of flexible synthetic material. Such a device is used in particular in the medical field for perfusion bags for example.

To access a flexible pocket, it is generally provided with a tube and a perforable access. In known manner, the tube is a flexible extruded tube (made of polyvinyl chloride for example) and cut to the desired length. It is generally attached to the flexible bag by welding. The perforable access is then fixed on the free side of the tube by gluing or by natural adhesion during steam sterilization for example. It has a thin perforable wall closing the access to the pocket and called the hymen.

To guarantee the sterility and inviolability of the access, the access device to the bag is generally provided with a protection. The latter is fixed so that it can only be removed by breaking or tearing.

For such devices, the welding of the tube on the pocket is difficult to achieve. Indeed, the end of the tube is placed in an opening made in the pocket and the edge of this opening is welded around the periphery of the tube. The weld therefore surrounds the tube. This is all the more difficult to realize that the tube is of small section.

The number of parts for making this type of access device is relatively large since some of these devices have four parts. The cost of production and assembly of these parts therefore increases the cost price of the device.

Patent application FR 94 02614 in the name of the Applicant describes a pocket comprising an access provided with a flat collar. Thanks to this, it is then possible to secure the tube on the flexible bag using a flat weld. This type of welding is easy to perform, but this solution does not make it possible to reduce the number of parts necessary to make the access device. In addition, when emptying a bag of flexible material equipped with a tube provided with a flat collar, there remains a non-negligible residual volume of liquid inside the bag.

The object of the invention is then to provide an access device to a pocket of flexible synthetic material, easily connectable to this pocket and produced in one piece, while guaranteeing sterility and inviolability of access to the pocket. Preferably, this access device also allows good emptying of the pocket on which it is fixed.

To this end, the access device that it offers is of the type comprising a flange mounted at a first end of an access tube as well as a thin, perforable wall, placed inside the tube and separating from watertight inside the tube in two areas.

According to the invention, the wall of the tube has a thinned annular zone placed between the thin perforable wall and the second end of the tube and this second end of the tube is closed by a weld.

The device thus obtained is therefore in one piece and guarantees sterility, thanks to the welding, and the inviolability of access to the bag, thanks to the thinned annular zone.

The thinned annular zone constitutes a tear initiation. To access the thin perforable wall, simply grasp the welded end and turn it relative to the rest of the tube. The torque thus exerted causes a tear or level in the thinned area. This operation is irreversible, it guarantees the inviolability of access to the flexible bag.

This access device is intended to be fixed on the fold of a pocket made of flexible synthetic material. When this pocket is filled, to allow better emptying thereof by the access device, the flange of the access tube is folded and has, perpendicular to this fold, a V-shaped section whose base is rounded.

In order to further improve the emptying of the bag, and this especially for bags of small volume, the internal face of the V of the collar follows the natural shape of a fold of a filled pocket on which is intended to be fixed. the access device.

To achieve a good weld and at the same time allow a good grip of the end of the tube to be torn, the latter is flattened in the shape of a duckbill. However, any other form of welding that may be carried out may be suitable.

The invention also proposes a method of manufacturing this access device. According to this mode, it is obtained by molding a tube comprising a flange at a first end, a thin perforable wall placed inside the tube and a thinned annular zone, then by welding the second end of the tube. This welding is preferably a high frequency welding.

• Figure 1 est une vue en perspective éclatée d'un dispositif d'accès et d'une poche représentée partiellement,
• Figure 2 est une vue de côté montrant le dispositif d'accès tel que fixé sur une poche,
• Figure 3 est une vue de face du dispositif d'accès et de la poche de la figure 2, l'extrémité du dispositif d'accès ayant été soudée, et
• Figure 4 est une vue à échelle agrandie de l'extrémité soudée du dispositif après sa désolidarisation avec le reste du dispositif.

In any case, the invention will be clearly understood with the aid of the description which follows, with reference to the appended schematic drawing, representing by way of nonlimiting example an access device according to the invention.

• FIG. 1 is an exploded perspective view of an access device and of a pocket shown partially,
• FIG. 2 is a side view showing the access device as fixed on a pocket,
• FIG. 3 is a front view of the access device and of the pocket of FIG. 2, the end of the access device having been welded, and
• Figure 4 is an enlarged view of the welded end of the device after its separation from the rest of the device.

Figures 1 and 2 show an access device 1 of thermoplastic material injection molded before it undergoes the operation of closing one of its ends by welding. Figures 3 and 4 show the same access device 1 once this welding has been carried out.

This access device comprises a tubular part, or tube 2, a thin wall 3 also called a hymen and placed transversely in the tube 2, a flange 4 produced at a first end of the tube 2 and a thinned annular zone 5. It is intended to be welded, thanks to the collar 4, to a pocket of flexible synthetic material 6 of polyvinyl chloride for example, at a fold 7 of this pocket 6.

The collar 4 has the general shape of a circular ring folded according to one of its diameters. Perpendicular to this diameter, it has a V-shaped section with a rounded base (Figure 2).

The angle formed by the two branches of the V, the curvature of the rounding are chosen so that the collar 4 conforms as best as possible to the fold 7 of the bag, when the latter is filled with liquid, for example perfusion liquid .

• engager à l'intérieur de la gaine un noyau conducteur de l'électricité présentant au moins une surface d'appui pour la zone de la gaine devant recevoir au moins une tubulure,
• positionner au moins un dispositif d'accès 1 sur la gaine, en un endroit de la gaine se trouvant sur la surface d'appui du noyau, la collerette 4 du dispositif étant au contact de la gaine,
• placer une première électrode cylindrique tubulaire sur chaque dispositif d'accès 1 à souder et une seconde électrode faisant face au noyau, la surface de la seconde électrode faisant face au noyau étant très supérieure à la surface de la première électrode faisant face au noyau.
• faire passer dans les deux condensateurs montés en série, constitués pour le premier, par la première électrode et le noyau séparés par la gaine et la collerette 4, et pour le second, par la seconde électrode et le noyau séparés par la gaine, un courant haute fréquence afin de souder la collerette sur la gaine,
• aplatir la gaine munie de dispositifs d'accès (1),
• souder transversalement la gaine aplatie formant ainsi les bords longitudinaux des poches,
• découper, éventuellement imprimer, remplir et fermer les poches obtenues.

The combination of a tube 2 with a flange 4 as described above and shown in the drawing is advantageously fixed to a pocket produced from a section of extruded cylindrical sheath and the two longitudinal edges of which are formed by the two ends of section of the extruded sheath closed by welding. It is carried out according to the following process which consists in:

• engaging inside the sheath an electrically conductive core having at least one bearing surface for the area of the sheath which must receive at least one tubing,
• positioning at least one access device 1 on the sheath, at a location in the sheath located on the bearing surface of the core, the collar 4 of the device being in contact with the sheath,
• placing a first tubular cylindrical electrode on each access device 1 to be welded and a second electrode facing the core, the surface of the second electrode facing the core being much greater than the area of the first electrode facing the core.
• passing in the two capacitors connected in series, constituted for the first, by the first electrode and the core separated by the sheath and the collar 4, and for the second, by the second electrode and the core separated by the sheath, a current high frequency in order to weld the collar on the sheath,
• flatten the sheath provided with access devices (1),
• transversely weld the flattened sheath thus forming the longitudinal edges of the pockets,
• cut out, possibly print, fill and close the pockets obtained.

High frequency welding can be replaced by thermal welding or by any other type of welding adapted to the materials used.

The shape of the core used, and in particular of the bearing surface, resumes the shape of the interior of a pocket filled with liquid.

Noticeably at mid-length of the tube 2, inside the latter, is the thin wall 3. The latter separates the interior of the tube 2 in leaktight manner into two zones: a first zone 8, on the side of the flange 4, is in connection with the interior of the pocket 6, the second zone 9 being in FIG. 2, in the open air.

Hymen 3 is perforable. It allows the passage of a trocar while ensuring sealing at the level of the outer surface thereof.

The second zone 9 of the tube carries the thinned annular zone 5 of the access device. This constriction constitutes a pre-tearing zone.

FIG. 3 shows the access device 1 in its final form, before use of the flexible bag 6. With respect to FIG. 2, the end of the tube 2, situated opposite the flange 4 beyond the thinned zone 5 is welded. It was flattened between two electrodes of a high frequency welding device and closed by welding. It then has a shape reminiscent of a duckbill.

The thinned zone 5 is not affected by the welding of the end of the tube 2. To then access the contents of the pocket 6, it suffices then to grasp the flattened and welded end 10 and to rotate it relative to the rest of the tube 2 to separate it at the level of the pre-tear zone 5.

The access device 1 described above has many advantages. First of all, it is made in one piece. This allows to have low manufacturing costs, but also avoids generating particles, since it is not necessary to make cuts to obtain such a device.

The collar 4 makes it possible to weld an access tube to a pocket using a "flat" weld. Even if the collar 4 is not flat, its welding does not have the drawbacks of an annular weld necessary for welding a tube without collar to a pocket.

The folding of the collar makes it possible to obtain a very good emptying of the pocket and to maintain the parallelism of the accesses when a pocket has several accesses.

Finally, the welding of the end of the tube and the thinned zone make it possible to guarantee the sterility and the inviolability of the access to the pocket on which the access device is welded.

It goes without saying that the invention is not limited to the embodiment of an access device described above by way of nonlimiting example; on the contrary, it embraces all its variants.

Claims (6)

Access device (1) to a pocket (6) of flexible synthetic material comprising a collar (4) mounted at a first end of an access tube (2) as well as a thin, perforable wall (3), placed inside the tube and sealingly separating the inside of the tube into two zones (8, 9), characterized in that the wall of the tube (2) has a thinned annular zone (5) placed between the thin wall perforable (3) and the second end of the tube and in that this second end of the tube is closed by a weld. Access device according to claim 1, characterized in that the collar (4) is folded and has a V-shaped section perpendicular to this fold, the base of which is rounded. Access device according to claim 2, characterized in that the internal face of the V of the collar (4) follows the natural shape of a fold (7) of a filled pocket, on which is intended to be fixed the device (1). Access device according to one of claims 1 to 3, characterized in that the welded end of the tube is flattened in the shape of a duckbill (10). Access device according to one of Claims 1 to 4, characterized in that it is obtained by molding a tube (2) comprising a collar (4) at a first end, a thin perforable wall (3) placed inside the tube and a thinned annular zone (5), then by welding the second end of the tube. Access device according to one of Claims 1 to 5, characterized in that the second end of the tube is closed by high frequency welding.

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