EP2702977B1 - Medical fluid container - Google Patents

Description

The present invention relates to a medical fluid container according to the preamble of claim 1.

Medical fluid containers are used for receiving and storing medical fluids or granules, for example, infusion fluids, blood plasma or the like. As a medical fluid container flexible film bag are known which define a certain internal volume in the filled state, since the foil bag is more or less brought out of its original form during filling and the filled content, so for example a medical fluid, in the bag builds up a voltage against the collapse , When suspended emptying through a tube with a small inner diameter of the content flows out and by the surrounding atmospheric pressure on the bag this takes on emptying its original collapsed, so flat two-dimensional shape. Of the originally filled fluid, only a small residue remains in the bag.

As a further design of medical fluid containers blow-molded bags are known which have a more or less spatial shape even in the unfilled state. The advantages of blow-molded pouches over the two-dimensional pouches include lower manufacturing costs, greater safety, d. H. Tightness, a lower production cost in the molding of ports (connections), etc.

An unsatisfactory in practice disadvantage of known blow-molded bags is a poorer idling behavior compared to foil bags.

If a blow-molded bag is emptied by gravity in a hanging manner over a hose with a small inner diameter analogously to a filled film bag, a negative pressure is created in the bag due to the more stable spatial shape of the blow-molded bag, since the decreasing fluid volume is due to the rigidity of the bag Bag can not or only partially compensated by a corresponding bag deformation. Finally, in the course of bag evacuation, a state is reached in which no further discharge of fluid out of the blow-molded bag is possible, so that a more or less large residual amount of fluid remains in the bag.

For complete emptying of a blow-molded bag would therefore be supplied in the course of the fluid discharge air in the bag, as is also known for glass bottles for the same purpose. However, the supply of air into the bag is excluded in a number of applications for reasons of hygiene.

It has therefore been forced when using blow-molded fluid containers to have to accept the remaining amount of fluid in the bag.

From the EP 0581724 A1 is a plastic bottle known, which is designed thin-walled and blown. The EP 0581724 A1 aims to make such a bottle foldable, so that it can be easily folded by hand in the deflated state and thus the waste volume can be reduced.

For this the beats EP 0581724 A1 before that fold lines are introduced into the material of the bottle wall. Along these fold lines a controlled folding of the bottle in its completely deflated state is then possible, with a bottle of the previously stabilizing residual stress of the bottle wall must be overcome. The arrangement or configuration of the fold lines is in this case such that a once folded bottle is quasi self-holding due to residual stresses which build up in curved wall sections, that is, a once folded bottle can not jump back into a deployed state.

A folding one according to the EP 0581724 A1 A trained bottle is only possible in its completely deflated condition, since mechanical (eg manual) pressure has to be applied from the outside to the completely emptied bottle in order to be able to apply it to the bottle to convert a collapsed state. Such a procedure is not applicable to the medical fluid containers in question.

From the EP 1 870 120 A1 Furthermore, a venous bag is known which consists of two flat films. The flat films are accordion-like connected on two opposite sides and provided at a central edge of the concertina section with a filament of an elastically deformable material. The filament sections are connected to a connecting section and ensure that the bag, when emptied, returns from the expanded state to the minimal volume state. The EP 1 870 120 A1 discloses a medical fluid container in the form of a flabby-walled foil bag with at least one Fluidbefüll- and removal device for pressure equalization free removal of fluid while collapsing a Behälterwandnut, wherein the container wall is formed with a collapse or predetermined bending line in the form of a Behälterwandnut, wherein the Behälterwandnut along a Main center plane which divides the container body into two substantially identical body halves and wherein the container wall groove is formed in the form of a depression or depression of the container wall.

From the pamphlets EP 1 663 100 B1 . EP 0 645 151 A1 and DE 2944558 A1 For example, other generic medical fluid containers of the prior art are known.

In contrast, the invention has the object of designing a medical fluid container in such a way that it is provided with a pressure-compensating-free, d. H. non-vented, removal under fluid while simultaneously collapsing a container wall is substantially completely emptied, although the container wall is self-supporting in the sense of a certain inherent stability, as is the case with fluid containers, which are produced by blow molding.

The object is achieved by a generic medical fluid container with the features according to claim 1, wherein the dependent claims have advantageous developments of the invention to the object.

The object of the present invention makes use of collapsing or predetermined bending lines in the form of a container wall groove, as is known from the already mentioned EP 0581724 A1 is known. However, in the subject matter of the present invention, the collapsing line or the container wall thickness inventively dimensioned therein ensures an independent and scheduled collapse of the container already exclusively as a result of gravitational outflow of the fluid from the fluid container.

In the subject matter of the present invention, therefore, the collapsing line in the container wall ensures that the fluid container automatically folds up exclusively as a result of a gravity-related outflow of the fluid. In contrast to the prior art thus does not serve the Kollabierknicklinie to fold the container after - usually more complete - emptying by a compressive force is applied to the container from the outside, but the Kollabierknicklinie allows an autonomous folding of the container due to or in the course of solely gravity-induced outflow of the fluid from the container.

When applied to a fluid container which was produced by the blow molding process, this means that the inventive design of the container with respect to the emptying behavior behaves like a fluff-walled film bag, but the disadvantages associated with a film bag and described at the outset are not met. In particular, it is possible with the medical fluid container of the present invention that a substantially complete emptying of the container without additional pressure equalization and without further aids is ensured, since the folding of the container is already exclusively due to the gravity alone flowing out of the fluid.

Arrangement and course and, if appropriate, the number of one or more collapsing or predetermined bending lines (container wall groove or container wall grooves) ultimately depend on the actual shape of the fluid container. Medical fluid container of the type in question are usually characterized by a "pillow shape", so in plan view are substantially rectangular and have an oval shape in cross-section. In such a configuration of the fluid container, the container wall groove extends substantially continuously along the entire container body periphery and along a main center plane which divides the container body into two substantially identical body halves. This course of the container wall groove ensures that two container wall sections are separated from one another by the container wall groove, which are substantially identical in terms of their area and with respect to their arrangement lie in such a way that collapsing of one body half in the direction of the other is possible without any resistance.

The container wall is film-hinge-like reduced or thinned at the transition between the container wall and the Behälterwandnut. This configuration makes the folding or collapsing operation of the container smoother.

According to a further and optionally independent aspect of the present invention, the container wall groove may be formed in a substantially semicircular cross-section. This embodiment of the Behälterwandnut ensures high pressure resistance and thus tightness despite reduced container wall thickness in this area on the one hand and easy, kink-free movements of the container wall sections in the Zusammenfaltbewegung. Furthermore, the configuration of the container wall groove or the container wall grooves, which is essentially semicircular in cross section, allows better demoulding of the finished fluid container when it is produced by the blow molding process.

The collapsing or folding process of the fluid container should ultimately ensure that the lowest possible, ideally substantially no amount of fluid remaining in the container, so this can be substantially completely emptied. In an ideal case, this can preferably be achieved completely by the fact that the inner surfaces of the two body halves essentially lie flat against each other during maximum folding of the container. In contrast to a floppy foil bag, no dead spaces in the form of gaps or bubbles remain between the two flat inner surfaces which fluid residues can hold, so that by this embodiment, an approximately complete emptying of the fluid container can be ensured.

Further details, aspects and advantages of the present invention will become more apparent from the following description with reference to the drawing.

• Fig. 1 schematisch und im Querschnitt eine Ansicht eines medizinischen Fluidbehälters im nicht kollabierten Zustand; und
• Fig. 2 eine Fig. 1 entsprechende Darstellung des Fluidbehälters im kollabierten oder zusammengefalteten Zustand.

It shows:

• Fig. 1 schematically and in cross section a view of a medical fluid container in the non-collapsed state; and
• Fig. 2 a Fig. 1 corresponding representation of the fluid container in the collapsed or collapsed state.

In the following description, the exemplary embodiment is based on the case that the medical fluid container is a plastic container which was produced by a so-called blow molding process and whose walls are self-supporting or intrinsically stable in the sense of maintaining the shape achieved in the manufacturing process even in the unfilled state.

The schematically simplified representation of the drawing shows a fluid container ("container") 1, which may be elongated / pillow-shaped in the illustrated embodiment, and thus the in Fig. 1 shown cross-section perpendicular to a longitudinal axis L of the container 1 may have. The container 1 is defined by a container wall 2 which is closed on all sides on the circumference, wherein at least one fluid filling and / or removal opening ("port"), not shown in the drawing, is located in the container wall 2. For containers of the type in question said opening or said port is usually arranged or formed on one of the two narrow or end sides of the elongated container 1.

The container wall 2 is formed on all sides gap-or joint-free fluid-tight and defined in the view of Fig. 1 a top or top wall 4, a bottom or bottom wall 6, a left side wall 8, and a right side wall 10 Terms "top" and "bottom" as well as "left" and "right" here in the context of the present description refer to the graphical representation of Fig. 1 ,

In the in Fig. 1 illustrated embodiment, the container 1 has a symmetrical with respect to a main center plane H structure with an upper container body half 12 and a lower container body half 14. The longitudinal axis L and the main center plane H intersect in the Fig. 1 apparent manner substantially centrally in the interior of the container. 1

The container wall 2 has at least one collapse or predetermined bending line in the form of a container wall groove 16. Said Behälterwandnut 16 extends at least partially in at least a portion of the container wall 2, d. H. in the upper wall 4 and / or the lower wall 6 and / or the left side wall 8 and / or the right side wall 10th

In the in Fig. 1 illustrated embodiment, the Behälterwandnut 16 is formed in the left side wall 8 and the right side wall 10 and is in this case in its altitude on the main center plane H, so that in each case the cross-sectional half of the Behälterwandnut 16 once on the side of the upper container body half 12 and once on the lower side Container body half 14 is located.

The Behälterwandnut 16 is formed in the form of a collection or indentation in the two side walls 8 and 10 and can in this case from Fig. 1 apparent, have approximately semicircular cross-section.

It is understood that with regard to the configuration of the Behälterwandnut 16 and / or with respect to their arrangement and / or course in one or more of the walls 4 to 10 no specific restrictions, such as according to the embodiment of Fig. 1 , present. Thus, the Behälterwandnut 16, for example, not only in one or the two side walls 8 and 10 extend, but may also / instead of in one or the two end walls of the container 1, not shown in the drawing (optionally with the recess of the local ports) extending running be. Likewise, for example, the one-sided or both sides, ie in one or in the two side walls 8 and 10 extending Sections of the Behälterwandnut 16 extend before reaching one or both end or end walls of the container 1 in the direction of the upper wall 4 and / or lower wall 6 and unite in the region of the upper wall 4 or lower wall 6. Furthermore, the cross-sectional shape of the Behälterwandnut 16 is not limited to the semicircular shape, but may, for example, a triangular shape or rectangular shape (polygon shape in general) have. The configuration of the container wall groove 16 in terms of number and / or arrangement and / or course is ultimately dictated by the shape of the container 1, the wall thickness (s) of the container wall or walls, the material used to produce the container 1 and by other factors or parameters ,

Due to the at least one collapse or predetermined bending line in the form of Behälterwandnut 16, it is possible to give the container 1 in the course of its emptying on the at least one port the behavior of a slack foil bag, that is, the container 1 can in the course of its emptying from his fully formed state with the cross-sectional shape of Fig. 1 in a nearly completely collapsed state according to the cross-sectional view of Fig. 2 be transferred.

In the course of the slow emptying of the filled container 1, a negative pressure builds up in the interior of the container 1, which due to the container wall groove 16, which serves as a collapse or predetermined bending line, causes the container 1 in the course of its emptying on or along the at least one container wall groove 16 collapses or collapses. The slow emptying of the container 1 takes place here as a rule by a purely gravity-induced outflow or leakage of the fluid from the container. 1

In a molding of the container 1 by a blow molding process, the container wall groove 16 or the container wall grooves 16 are formed simultaneously with the formation of the container wall 2 with their respective extensions, arrangements and cross sections. At transition lines or transition edges 18 between the container wall 2 and the Behälterwandnut 16, the material of the container wall 2 is film-hinge-like thinner, since in the region of these transitions 18 a changed flow behavior of the plastic material in the course of production of the container 1 and the container wall 2 results. These thinned portions in the region of the container wall groove 16 allow the container 1 in the course of Gravity-related evacuation collapses or collapses, as in Fig. 2 shown, wherein an additional bending or deflection of the individual container wall sections with each other in the region of the Behälterwandnut 16 and the local transitions 18 takes place.

In the completely deflated condition, d. H. at maximum folding or collapsing of the container 1, preferably an inner wall 20 of the upper container wall 4 with an inner wall 22 of the lower container wall 6 is substantially completely in flat contact. Ultimately, only minor residual volumes remain 24 on both sides of the contact area between the two inner walls 20 and 22. Due to the still existing material inherent stiffness of the upper wall 4 and the lower wall 6 whose inner walls 20 and 22 are substantially flat, d. H. gap-free, to one another, so that substantially no fluid residues can be left between the two walls 4 and 6.

The degree of emptying of the collapsed container 1 in the illustration of Fig. 2 thus essentially corresponds to that of a flaccid foil bag or even able to exceed it.

The object of the present invention thus makes it possible in summary to obtain the advantages of a blow-molded container for fluids, in particular medical fluids, completely. These advantages are in particular the low cost of the blow molding process for the production of the container 1 with simultaneous formation of the at least one port in the container wall 2 without leakage problems. The previous disadvantages of such a container, namely in particular the incomplete emptying without additional measures for pressure equalization in the container interior are eliminated because due to the Behälterwandnut 16 of the container 1 in the course of its gravitational or gravity-induced emptying independently and scheduled collapses or collapses such that only a small residual volume remains in the container interior.

A medical fluid container (1) with at least one Fluidbefüll- and - removal opening for pressure equalization-free removal of fluid while simultaneously Collapsing of a container wall (2) is characterized in that the container wall (2) is formed with at least one collapse or predetermined bending line in the form of a container wall groove (16), in which the remaining container wall thickness an independent and scheduled folding of the container (1) already exclusively as a result of a gravity-induced outflow of the fluid from the fluid container (1) ensured. Upon complete collapse, inner surfaces (20, 22) of two body halves (12, 14) may lie substantially flat against one another. The substantially complete emptying of the container without internal pressure compensation in the manner of a flexible / flaccid foil bag is thus ensured, even if the container (1) or its container wall (2) is produced by blow molding and thus a certain inherent rigidity in terms of maintaining the internal volume even when empty shows.

Claims (3)

1. Medical fluid container (1) in the form of a foil bag with slack walls having at least one fluid filling and withdrawal opening for withdrawal of fluid without pressure equalization while simultaneously collapsing a container wall (2), characterized in that the container wall (2) is formed with a collapsing or target fold line in the form of a container wall groove (16) in which the remaining container wall strength, preferably at the groove bottom, guarantees automatic as well as planned folding of the container (1) already exclusively as a result of a gravity-related flowing out of the fluid from the fluid container (1), wherein the container wall groove (16) extends essentially continuously around the whole container body circumference along a main center plane (H) which divides the container body into two, essentially identical body halves (12, 14), wherein the container wall groove (16) is configured in the form of a retraction or indention of the container wall, and wherein the container wall strength is reduced at a transition (18) between the container wall (2) and the container wall groove (16) in a film-hinge like manner.
2. Container (1) according to claim 1, characterized in that the container wall groove (16) has an essentially semi-circular cross-section.
3. Container (1) according to claim 1 or 2, characterized in that when the container (1) is maximally folded, the inner surfaces (20, 22) of the two body halves (12, 14) essentially come to lie flatly against each other.

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