Patent Application
20100150480
The present application claims priority from French Patent Application No. FR 08 58587, filed in the French Patent Office on Dec. 15, 2008, the entire content of which is incorporated herein by reference.
The present invention relates to a sachet for packaging a biological liquid substance, such as animal semen.
It also relates to a strip formed by juxtaposition of such sachets.
In the field of animal artificial insemination, pigs in particular, it is familiar to package semen—boar in this case—into sterile sachets.
These sachets are formed by two coupled and welded films of flexible plastic material, generally by thermo-welding, delimiting a reception pouch of the substance.
The sachets are filled on a machine specially adapted to this usage, in which the strip of sachets files past gradually.
The sachets are suspended in a vertical position such that their filling opening is facing up.
The preferred dose of substance is delivered by means of a hollow needle, via a flexible feed conduit, one end of which is connected to a container containing the substance and the other to the hollow needle; the conduit is equipped with a peristaltic pump which ensures precise distribution of the doses.
At the time of filling, the strip of sachets is stopped, and the needle, which is also vertical, penetrates the opening of the sachet to be filled and descends inside the pouch, to around mid-height thereof, or even lower; the dose of substance is injected into the sachet via the lower end of the needle, then the needle is withdrawn via vertical movement from bottom to top, after which the opening zone is sealed by thermo welding.
The operation is then repeated on the following sachet.
Later, when insemination takes place, the substance is repelled from the sachet and fed to the insemination probe, either via this same opening, after opening of the welded zone, or by means of a canula arranged at the end opposite the sachet, for example in keeping with the teachings of document EP-B-1 317 224.
When it is porcine semen, the substance is composed of boar sperm mixed with a diluent containing preservatives such as sugars, citrates and albumin, which cause the substance to foam.
The formation of foam at the time of filling is promoted by the relatively high rate of the substance as it leaves the needle, with a strong rate being necessary for filling the sachets to be completed at an appropriate rate (generally approximately 2 seconds per sachet).
This foam has a tendency to adhere to the needle and go with it as it is withdrawn in the opening zone where welding must be done, or even beyond this zone.
A fraction of the semen is therefore withdrawn from the sachet, which is not satisfactory for dosage precision.
Also, the presence of this foam in the opening zone compromises the quality of the welding and consequently the tight seal of the now-filled sachet.
Finally, the possible presence of semen outside the sachet is a possible cause of unwanted transfer of spermatozoids from one sachet to another within a batch of filled sachets stored side by side; the liquid leaving the sachet also risks altering the marking, by dilution of ink, this which can especially cause difficulties for reading identifying labels.
Document WO 94/22731 discloses a sachet structure for packaging a liquid material, which comprises sealing means arranged such that, even if the sachet is full and not connected to a discharge conduit, there is no risk of loss of liquid through its discharge opening. Also, WO 02/32469 relates to a sachet for packaging liquid material, and more precisely a technique for inactivating pathogenic agents in fluids such as blood.
According to this technique, the sachet is filled by means of one or more openings, optionally pre-connected to tubing and this opening is then sealed so as to constitute a tight joint around said opening.
The aim of the present invention is to resolve the difficulties indicated above by preventing the formed foam from accompanying the injection needle as it is withdrawn from the filling opening of the sachet.
The invention therefore relates to a sachet for packaging a biological liquid substance, such as animal semen, formed by two coupled and welded films of flexible plastic material, delimiting a reception pouch of the substance, which has at one of its ends an opening for filling the empty sachet by means of a hollow cylindrical needle.
According to the invention, these films have a pair of mutual welding lines which form tabs starting out from said opening and axially and symmetrically penetrating the internal space of the sachet by converging towards the interior of the latter, their free ends being moved apart from one another. They have a value “e” which is substantially equal to πd/2, “d” being the value of the diameter of said needle, introduced into the sachet for filling.
In this way, the needle passes between the tabs for filling of the sachet, and the latter ensure scraping of the needle when it is being withdrawn.
Due to this arrangement it is understood that when the needle passes between the two tabs and penetrates the sachet by axial translation movement, from top to bottom, this zone deforms and matches the circular contour of the needle; in fact, the circumference of the zone, when deployed to be “rounded”, is equal to 2e, or πd, corresponding to the circumference of the needle.
When on completion of filling, the needle is withdrawn by an axial translation movement, this time from bottom to top, the periphery of this circular and narrowed zone retains the foam which adheres to the cylindrical wall of the needle and orients it laterally to the exterior with a scraping effect; the foam thus remains imprisoned in the sachet, below the welding lines formed by tabs.
The two welding lines preferably converge by forming an angle at the apex of which the value α is between 20 and 60°, advantageously close to 45°, which causes particularly efficacious scraping and cleaning of the needle.
According to other possible, though non-limiting, advantageous characteristics of the invention:
the filling opening of the sachet has, turned to the exterior of the sachet, an orifice zone of constant width “a”, substantially larger than said spread value “e” of the free ends of the welding lines;
this orifice zone is delimited on either side by a welded area each traversed by an orifice in which a retaining finger can engage during filling of the sachet;
the two welding lines have a reinforced end, for example formed by a bead;
the end opposite the sachet is fitted with an integrated canula, to be used for emptying out the sachet.
Another aim of the invention is a strip of sachets formed by juxtaposition of sachets having the preceding characteristics, which are adjacent to one another and separated by a pre-cut-out line.
Other characteristics and advantages of the invention will emerge hereinbelow from the description of a preferred embodiment of the invention. This description is given in reference to the attached diagrams, in which:
The sachet 1 illustrated in
As is well known, it is made from two thin and supple (flexible) films of thermo-weld plastic material, superposed then welded to one another, forming a strip B.
Each sachet has a general rectangular elongated form, whereof the large axis of symmetry is designated X-X′. Its contour is delimited by two lateral welded borders 10, a first closed end zone 11 (bottom), also welded, and a second end zone comprising two welded zones 12a, 12b separated by an opening 4 for filling.
This plastic material is preferably transparent or translucid and constituted for example by polyethylene, polyamide or polyethylene terephthalate (PET).
The two films are preferably constituted by two distinct sheets. However, one and the same sheet, which is folded back on itself, can be used.
Each sheet can be mono-layer or multi-layer
The sachet 1 is separated from the two adjacent sachets 1A and 1B by pre-cut lines 100A, respectively 100B, connecting end perforations 101-102, as is well known.
In the zones 12a and 12b, orifices 3, 3′ are pierced which serve to receive driving fingers and retaining fingers of the sachets, in suspended position, in the filling machine.
According to a known arrangement, one 3′ of these orifices has an oblong form, being formed by two circular holes partially overlapping.
In the bottom zone 11, an emptying canula 2 is integrated, of axis X-X′, integrated into the sachet, for example in keeping with the teachings of document EP-B-1 317 224.
The longitudinal edges of the strip, outside the zones 12a-12b and the filling opening 4 are disassembled (not welded) and can therefore be freely moved away from one another.
The opening 4 has a principal portion 6 conventionally designated as “orifice”, delimited by the edges vis-à-vis the welded parts 12a and 12b, edges which are parallel to the axis X-X′ and spaced at a distance “a”. These edges are prolonged inside the sachet by welding lines 7, formed by rectilinear tabs. The latter are inclined symmetrically relative to the median axis X-X′ so as to converge towards the interior of the sachet, forming a “V” with cut-off point.
They form an angle at the apex α whereof the value is advantageously approximately 45°.
Their free ends are distant by a value “e” substantially less than “a”.
This value “e” is adapted to the diameter “d” of the hollow needle used for filling, such that when the needle axially traverses the opening 6, it pushes back the plastic film zones about this narrowed passage, referenced 70 in
During the filling operation of the sachet, the latter is suspended in the filling machine on retaining fingers R and R′ which are engaged in the above orifices 3 and 3′, as illustrated in
The width “a” of the orifice zone 6 is notably larger than the diameter “d” of the needle 8.
Therefore, during the axial descent of the needle 8, according to X-X′, in the orifice 6, the latter pushes back the portions of opposite film and easily causes this zone to move away, in spite of the tension due to the presence of the retaining fingers R and R′.
Any risk of piercing or tearing of the sachet at this level is practically eliminated.
Continuing this descending movement, its end portion is guided gently and progressively by the tabs 7, passes through the “rounded” zone 70 without notable play, then penetrates inside the sachet.
It generally descends as far as mid-height of the sachet, or even lower, after which the dose of semen—referenced S—is injected inside the sachet, swelling it by giving it the form of a pouch, and generating foam at the same time.
On completion of filling, the needle 8 is withdrawn via an axial translation movement from bottom to top, symbolised by the arrow F in
The reference M designates foam adhering to the wall of the needle 8. The ends of the tabs 7, such as supple lips, as well as the edges of plastic film to the right of the narrowed passage 70 scrape this wall and hold back the foam M by deflecting it laterally under the oblique welding lines 7, as indicated by arrows G. The foam therefore remains trapped inside the sachet, without fouling the orifice 6, as per the desired aim.
The filling opening is then blocked tightly, in good conditions, by a thermo-welding line 9.
In the variant illustrated in
The presence of the beads 71 reinforces the end of the tabs by limiting the risks of incipient breakage at this level when the sachet is subjected to high mechanical constraints, especially by torsion, in view of its emptying out during insemination (via the canula 2).
The variant 5 illustrates another possible mode of sealing the sachet after filling.
In this variant, the interior of the opening 6, as well as the portion situated above and between the tabs 7, are sealed by a thermo-welded area 9′. But this sealing is partial only, retaining a non-welded central passage 91.
Towards the exterior, this passage opens via a V-profiled zone 90.
This passage is in turn sealed by a peelable area 9″.
Because of this arrangement the filling opening 4 can also be utilised for emptying out, which is useful especially for sachets with closed bottom, such as described for example in document FR-A-2 667 504.
After opening of the peelable portion, the passage 91 uses an emptying out conduit and the centring cone portion 90 for placing the insemination probe.
The configuration of the filling opening and the presence of the tabs make for use of a needle with a straight end (perpendicular to the axis of the needle), simply slightly chamfered and blunted.
In general, conventional sachets utilise a bevel-cut needle end facilitating its introduction into the sachet, but which risks pouring a small quantity of substance retained in the needle after it is withdrawn from the bag.
The following dimensions are given purely by way of indicative example:
internal contour of the sachet: 190 mm×60 mm
a=20 mm
e=8 mm
d=5 mm
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 08 58587 | Dec 2008 | FR | national |
