FR2732317A1 - DEVICE FOR ACCESSING A POCKET IN FLEXIBLE SYNTHETIC MATERIAL - Google Patents

Abstract

This access device comprises a collar (4) mounted at a first end of an access tube (2) as well as a thin wall (3), perforable, placed inside the tube and sealingly separating inside the tube into two zones. The wall of the tube has a thinned annular zone (5) placed between the thin perforable wall (3) and the second end of the tube and the latter is closed by a weld. The access thus achieved is one-piece. If, moreover, the collar is folded and has a V-shaped section perpendicular to this fold, the base of which is rounded, then the access allows very good emptying of the pocket (6) on which it is fixed.

Description

The present invention relates to a device for accessing a pocket in

  flexible synthetic material. Such a device is particularly

  used in the medical field for infusion bags for example.

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

pocket and called hymen.

  To ensure the sterility and the inviolability of the access, the access device to the pocket is generally provided with a protection. The latter is so fixed that it can only withdraw by rupture or by

tear.

  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 to the periphery of the tube. The solder thus surrounds the tube. This one is

  all the more difficult to realize that the tube is of small section.

  The number of parts to make this type of access device is relatively important since some of these devices have four parts. The cost of production and assembly of these parts increases

  therefore the cost price of the device.

  The patent application FR 94 02614 in the name of the Applicant describes a pocket having an access provided with a flat flange. With this, it is then possible to fix the tube on the flexible bag with a flat weld. This type of welding is easy to achieve, but this solution does not reduce the number of parts needed 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 significant residual volume of

  liquid inside the pocket.

  The object of the invention is then to provide a device for access to a flexible plastic bag, easily connectable to this bag and made in one piece, while ensuring the sterility and inviolability of access to the poached. Preferably, this access device

  also allows a good emptying of the pocket on which it is fixed.

  For this purpose, the access device it proposes is of the type comprising a flange mounted at a first end of an access tube and a thin wall, perforable, placed inside the tube and

  sealingly separating the inside of the tube into two zones.

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

  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 the access to the pocket, thanks to

to the thinned annular zone.

  The annular thinned zone constitutes a tear initiation.

  To access the perforable thin wall, simply grasp the welded end and turn it relative to the rest of the tube. The thus exercised torque causes a tear or level of the thinned area. This operation being irreversible, it makes it possible to guarantee the inviolability of the access

at the soft pocket.

  This access device is intended to be fixed on the fold of a flexible plastic bag. When this bag is filled, to allow a better emptying thereof by the access device, the collar of the access tube is folded and presents perpendicular to this

  fold a V-shaped section whose base is rounded.

  In order to further improve the emptying of the pocket, and this especially for pockets of small volume, the inner face of the V of the collar matches 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 tear tube, the latter is flattened in the shape of a duckbill. However, any other form of welding achievable

may be suitable.

  The invention also proposes a method of manufacturing this access device. In this mode, it is obtained by molding a tube having a collar at a first end, a perforable thin wall placed inside the tube and a thinned annular zone, and then welding the second end of the tube. This weld is

  preferably a high frequency welding.

  In any case, the invention will be well understood by means of the

  description which follows, with reference to the attached schematic drawing,

  representative by way of non-limiting example an access device according to the invention. Figure 1 is an exploded perspective view of an access device and a pocket partially shown, Figure 2 is a side view showing the access device as attached to a pocket, Figure 3 is a front view of the access device and the pocket of Figure 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 injection molded thermoplastic material 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

completed welding.

  This access device comprises a tubular part, or tube 2, a thin wall 3 also called hymen and placed transversely in the tube 2, a flange 4 made at a first end of the tube 2 and a thinned annular zone 5. It is intended to be welded, thanks to the flange 4, to a flexible plastic bag 6 made of polyvinyl chloride

  for example, at a fold 7 of this pocket 6.

  The flange 4 has a general shape of circular ring bent according to one of its diameters. Perpendicular to this diameter, she

  has a V-shaped section whose base is rounded (Figure 2).

  The angle formed by the two branches of the V, the curvature of the rounded are chosen so that the flange 4 matches as best as possible the fold 7 of the pocket, when it is filled with liquid, the liquid of

infusion for example.

  The combination of a tube 2 with a collar 4 as described above and shown in the drawing is advantageously fixed on a pocket made from an extruded cylindrical sheath section and whose two longitudinal edges are formed by the two ends of the section. extruded sheath closed by welding. It is carried out according to the following method which consists of: - engaging inside the sheath an electrically conductive core having at least one bearing surface for the zone of the sheath to receive at least one tubular, - positioning at least one access device 1 on the sheath, at a location of the sheath 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 an access device 1 to be welded and a second electrode facing the core, the surface of the second electrode facing the core being very

  greater than the surface of the first electrode facing the core.

  - pass in the two capacitors connected in series, constituted for the first, by the first electrode and the core separated by the sheath and the flange 4, and for the second, by the second electrode and the core separated by the sheath, a high frequency current in order to weld the flange to the sheath, - to flatten the sheath provided with access devices (1), - to weld transversely the flattened sheath thus forming the longitudinal edges of the pockets, - to cut, possibly to print, to fill and to close the

pockets obtained.

  High frequency welding can be replaced by thermal welding or any other type of welding suitable for

materials implemented.

  The shape of the core used, including the bearing surface

  takes the shape of the inside of a pocket filled with liquid.

  Substantially mid-length of the tube 2, inside thereof, is the thin wall 3. The latter tightly separates the inside of the tube 2 into two zones: a first zone 8, on the side of the flange 4, is in connection with the inside of the pocket 6, the second zone 9

  being in Figure 2, in the open air.

  The hymen 3 is pierceable. It allows the passage of a trocar

  while ensuring the seal at 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-tear 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 collar 4 beyond the thinned zone is welded. It was flattened between two electrodes of a high-frequency welding machine and closed by welding. She then presents a

  shape reminiscent of that of a duckbill.

  The thinned zone 5 is not affected by the welding of the end of the tube 2. In order then to access the contents of the pocket 6, it is then sufficient to grip the flattened and welded end 10 and to turn it relative to the rest of the tube 2 to separate it at the level of the zone

pre-tear 5.

  The access device 1 described above has many advantages. First, it is made in one piece. This makes it possible to have low manufacturing costs, but also avoids generating particles, because it is not necessary to make cuts to obtain

such a device.

  The flange 4 makes it possible to weld an access pipe to a pocket by means of a "flat" weld, and even if the flange 4 is not flat, its weld does not have the drawbacks of a weld.

  ring necessary to weld a tube without flange 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 multiple access

  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 soldered.

  It goes without saying that the invention is not limited to the embodiment of an access device described above as a non-exemplary example.

  limited; on the contrary, it embraces all variants.

Claims (6)

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