U.S. patent application number 10/499814 was filed with the patent office on 2005-04-14 for flexible container having an access port, method for the production of said container and welding tool for implementing said method.
Invention is credited to Kugelmann, Franz.
Application Number | 20050078887 10/499814 |
Document ID | / |
Family ID | 27674719 |
Filed Date | 2005-04-14 |
United States Patent
Application |
20050078887 |
Kind Code |
A1 |
Kugelmann, Franz |
April 14, 2005 |
Flexible container having an access port, method for the production
of said container and welding tool for implementing said method
Abstract
The invention relates to the area of flexible containers in
which an access port is provided toward the interior of the
container. To increase the stability of such a container (1) at the
position of the access port (4), the invention provides that the
connection seam (2) connecting the access port (4) to a flexible
foil is prolonged in the direction of a section (4a) of the access
port (4) projecting over the connection seam (2) in order likewise
to connect a part (5) of this section (4a) of the access port (4)
to the foil. It is achieved by this measure that the peeling forces
particularly effective in this region in the event of a pressure
load are countered better. The invention also relates to a method
for the manufacture of such a flexible container and to a welding
tool for this.
Inventors: |
Kugelmann, Franz; (St.
Wendel-Bliesen, DE) |
Correspondence
Address: |
JACOBSON HOLMAN PLLC
400 SEVENTH STREET N.W.
SUITE 600
WASHINGTON
DC
20004
US
|
Family ID: |
27674719 |
Appl. No.: |
10/499814 |
Filed: |
July 1, 2004 |
PCT Filed: |
January 24, 2003 |
PCT NO: |
PCT/EP03/00741 |
Current U.S.
Class: |
383/107 ;
383/904; 383/906 |
Current CPC
Class: |
B29C 65/18 20130101;
B29L 2031/7148 20130101; A61J 1/10 20130101; B29C 66/133 20130101;
B29C 66/53262 20130101; B29C 66/1122 20130101 |
Class at
Publication: |
383/107 ;
383/904; 383/906 |
International
Class: |
B65D 030/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 18, 2002 |
DE |
10206738.4 |
Claims
1. A flexible container (1) having an access port (4) in which a
flexible foil and a second area-like boundary part are connected to
one another along a connection seam (2) and wherein the connection
seam (2) passes over an access port (4) which is arranged between
the foil and the boundary part and represents an access from the
exterior of the container to the interior of the container, wherein
the access port (4) has a section (4a) which projects over the
connection seam (2) in the direction of the interior of the
container, characterized in that the connection seam (2) is
prolonged at the position, at which it connects the access port (4)
to the foil, in the direction of the projecting section (4a) of the
access port (4) to likewise connect a part (5) of this section (4a)
of the access port (4) to the foil.
2. A flexible container in accordance with claim 1, wherein the
second area-like boundary part is likewise a flexible foil.
3. A flexible container in accordance with claim 1, wherein the
access port (4) is a hose.
4. A flexible container in accordance with claim 1, wherein the
access port is a boat-like insert having at least one access
opening.
5. A flexible container in accordance with claim 1, wherein the
container is formed from a folded over piece of foil as well as of
one longitudinal connection seam and two transverse connection
seams, with the access port being arranged in one of these
connection seams.
6. A flexible container in accordance with claim 1, wherein the
container (1) is made from a hose foil and two transverse
connection seams (2, 3), with the access port (4) being arranged in
one of these connection seams.
7. A flexible container in accordance with claim 1, wherein the
connection seams (2) are weld seams.
8. A flexible container in accordance with claim 1, wherein the
connection seams (2) are adhesive seams.
9. A flexible container in accordance with claim 1, wherein the
part (5) of the connection seam (2) which partly connects the
projecting section (4a) of the access port (4) to the foil is made
in tab shape.
10. A flexible container in accordance with claim 9, wherein the
tab-like prolongation (5) of the connection seam (2) has a section
which corresponds to the intersection line between a semi-circular
groove (11) and a plane (12) extending at an incline to the groove
by an acute angle --preferably by 30 to 60 degrees.
11. A method for the insertion of an access port (4) between a
flexible foil and a second area-like boundary part of a flexible
container (1), wherein the access port (4) is positioned between
the foil and the boundary part, the foil and the boundary part are
connected to one another along a connection seam (2) which passes
over the access port (4), with the access port (4) projecting over
the connection seam (2) by a section (4a) in at least one
direction, characterized in that the foil and parts (5) of the
projecting section (4a) of the access port (4) are connected to one
another as a part of the connection seam (2).
12. A method in accordance with claim 11, wherein the connection
seam (2) is welded.
13. A welding tool (10) for the carrying out of the method in
accordance with claim 12 which consists of a block-like substrate
which has a groove (11) extending in a first surface (13) and
having the contours of the access port (4), with both the first
surface (13) and the contours of the groove (11) being made as
heating surfaces for thermal contact welding, characterized in that
the groove (11) is bounded by a second surface (12) of the
substrate which has a acute angle of inclination to the first
surface (13).
14. A welding tool in accordance with claim 13, wherein the groove
(11) has a semi-circular section for the reception of the
longitudinally extending half of an access port (4) formed as a
hose.
15. A welding tool in accordance with claim 13, wherein the acute
angle of inclination lies between 30 and 60 degrees.
Description
[0001] The invention relates to the field of flexible containers in
which an access port to the interior of the container is provided,
to a method for the manufacture of such a container and to a
welding tool for the carrying out of such a method.
[0002] Flexible containers, in particular pouches, which are
manufactured from thermoplastic foil material, are widespread in
various areas of application. For many applications, the flexible
container has at least one access port which leads from the
exterior of the container to the interior of the container and
which serves for the emptying and/or for the filling of the
container.
[0003] Such containers can be manufactured without great effort and
at a low price, in particular as pouches. They can therefore be
used without problem in medical applications as mass-produced
articles with a disposable character. The pouch can be pre-filled
with a liquid such as an infusion fluid or a dialysis fluid. Empty
pouches are also used in order e.g. to be able to accept a liquid
during a medical treatment.
[0004] In the simplest case, a hose can serve as the access port
which is e.g. welded between two foils. The transition point of the
connection seam, at which it, starting from the connection
foil-to-foil, encounters the connection foil-to-hose, must
withstand enormous strains in this process. Loads can occur due to
high pressure waves after the falling of the pouch (fall strength)
or also during proper use (e.g. hydrostatic pressure, infusion with
pressure cuff). Such loads can result in the bursting or tearing of
the pouch, with said transition point being the starting point for
such damage in many cases.
[0005] Devices are also known to increase the stability in the
region of the access port in which a boat-like insert is provided
as the access port at which a usually rigid plastic body is
centrally penetrated by an opening which serves as an access
opening. Tapering prolongations adjoin it. The foils undergo a more
constant, tangential extent at the transition point in this manner.
While such an insert increases the stability, it is, however, more
complex in handling and is associated with higher costs.
[0006] A foil pouch having a hose-like access port is described in
EP 0 269 419 B1 in which, after the welding of the pouch, a
tube-like cuff is applied around the hose port and the foil
surrounding it in an injection molding step. This requires a
further production step as well as additional material, which is in
particular disadvantageous for an application in high volumes.
[0007] It is therefore the underlying object of the invention to
increase the stability of a flexible container at the position of
an access port, without this being accompanied by a real increase
in effort and material costs.
[0008] The solution of this object takes place with the features of
the characterizing portion of claim 1. Advantageous aspects are
named in the subordinate claims dependent on this claim.
[0009] The invention is based on the observation that, on the
introduction of a three-dimensional access port between two
two-dimensional boundary areas such as foils, problems result with
respect to the exact unwinding of the boundary areas onto the
surface of the access port. This can be illustrated most clearly
with reference to an access port made as a hose which is laid
between two foils and in which a connection seam between the foils
extends directly over the hose. The extent of the container or of
the pouch present along the connection seam is reduced due to the
hose running around along half of its periphery in each case. This
reduction is, however, no longer present directly subsequent to the
hose end which opens into the pouch. The hose usually
projects--likewise for technical production reasons--into the
interior of the pouch.
[0010] In the transition zone between the connection seam and the
end of the hose, a tab-like zone is formed next to the welding seam
in the event of a load, which can be caused solely by filling, with
the foil contacting the hose in said zone. The foil only
subsequently lifts off from the hose. The stability in this region
can therefore be increased by an additional connection of the
tab-like zone to the hose, without this being accompanied by a loss
in volume, such as would the be case with a simply broadened
welding seam. In addition, the force component which causes a
peeling off at the transition from the foil to the hose in the
event of a load (the pouch "tries" to enlarge the available width)
is opposed by a force component which extends along the hose axis
and thus perpendicular to the expansion force. Ultimately, it is
thus relevant within the framework of the invention that the
connection seam covers part of the section of the access port which
projects into the container. The connection seam in this process
projects on this section of the access port further into the
interior of the container than in the region of the connection seam
directly adjoining the access port at the side.
[0011] This measure only requires a simple modification of the
welding tool; an additional production step is not necessary. Since
the stability of the container is increased, it is even possible to
reduce the wall thickness of the container material when required
and thus to save material, provided the container thus present
meets required specifications.
[0012] It lies within the framework of the invention that the
flexible container in accordance with the invention consists of
different area-like boundary parts wherein at least one is formed
as a flexible foil and the access port is inserted between this
foil and a second area-like boundary part.
[0013] In an advantageous embodiment, the second area-like boundary
part is likewise a flexible foil.
[0014] In the simplest case, the access port is made as a hose.
However, the invention also includes differently shaped access
ports such as boat-like inserts.
[0015] In a further embodiment of the invention, in which the
access port is inserted between two flexible foils, the flexible
container consists of a folded piece of foil as well as of one
longitudinal connection seam and two transverse connection seams,
with the access port being arranged in one of these connection
seams.
[0016] In an embodiment which is particularly easy to handle, the
flexible container consists of a hose foil and two transverse
connection seams, with the access port being arranged in one of
these connection seams.
[0017] All forms of permanent connection processes are available
for the connection seams. In particular welding seams and adhesive
seams can be named here, with welding having particular importance
due to the technical production advantages.
[0018] The most varied materials can serve as the starting material
for the flexible foil of the pouch, provided they are suitable for
the manufacture of connection seams with the materials to be
connected. In most cases, these will be thermoplastics. It is,
however, also feasible to use correspondingly thin metal foils.
[0019] It is also the underlying object of the invention to provide
a method for the insertion of an access port between a flexible
foil and a second area-like bordering part of a flexible container
for the manufacture of a flexible container in accordance with the
invention. The solution of this object is achieved by the features
of the characterizing portion of independent claim 11.
[0020] It is likewise the underlying object of the invention to
provide a welding tool for the carrying out of the method in
accordance with the invention for the manufacture of a flexible
container in accordance with the invention. The solution is
achieved with a welding tool having the features of the
characterizing portion of independent claim 12.
[0021] EP 1 072 531 A2 shows a flexible container having an access
port designed as an access port in which diverse incisions are
provided for the tearing and releasing of the hose port. In
addition, the connection seam, which is present between two foils
and extends over the inserted hose, is broadened in the direction
of the part of the hose projecting into the container. This
broadening also extends, however, transversely to the hose, i.e.
also in the adjoining region, where it directly connects the two
foils to one another.
[0022] An exemplary embodiment of the invention is described in
more detail in the drawings. There are shown:
[0023] FIG. 1 a flexible container made as a hose pouch with an
access port provided as a hose in accordance with the prior
art;
[0024] FIG. 2a an enlarged representation of the access port of
FIG. 1;
[0025] FIG. 2b an enlarged representation of the access port of
FIG. 2a in accordance with an embodiment of a flexible container in
accordance with the invention;
[0026] FIG. 3a the side view of an embodiment of a welding tool in
accordance with the invention; and
[0027] FIG. 3b the welding tool of FIG. 3a in a plan view.
[0028] In FIG. 1, a flexible container 1 in accordance with the
prior art is shown which was manufactured from a hose foil. The
flexible container or pouch 1 is closed by two transverse welding
seams 2 and 3 (drawn in hatched manner). An access port made as a
hose 4 is provided in the connection seam 2 and is drawn in a
slightly perspective manner in this Figure for reasons of
illustration. The pouch 1 is filled with a medium which is not
shown in any more detail, whereby a slight tapering of the pouch at
the pouch center results in plan view. In this case, the access
port is closed by a seal, likewise not shown in any more detail,
which can be opened by a user if required.
[0029] A section 4a of the hose 4 projects beyond the connection
seam 2 into the interior of the container. Due to the filling of
the pouch, the foil material nestles along the line extending in a
broken line in a region 5 against the section 4a of the hose,
although the connection seam 2 does not include this region.
[0030] The access port is shown enlarged in FIG. 2a, with the
perspective illustration of the hose 4 not having been taken over.
The tap-like region 5 on the hose section 4a is clearly
recognizable.
[0031] FIG. 2b shows this region for an embodiment of a flexible
container in accordance with the essence of the patent. The
connection seam 2 now also includes the tab-like region 5. This can
absorb additional forces in order to increase the stability of this
region of the pouch. The available pouch volume remains practically
unchanged.
[0032] In FIGS. 3a and 3b, an embodiment of a welding tool, with
which an access port as shown in FIG. 2b can be inserted between a
flexible foil and a second areal-like boundary part of a flexible
container, is shown in a side and plan view. For this purpose, a
block-like substrate body 10 is provided which has a first surface
13 into which a groove 11 with a semi-circular section has been
inlet. The radius of the semi-circle results from the radius of the
hose 4 to be welded in.
[0033] The block-like substrate body moreover has a second surface
12 which is inclined by an acute angle .alpha. with respect to the
direction in which the groove 11 or the first surface 13 extends.
The substrate body, in particular the area of the groove 11 and the
first surface 13, can be heated for thermal contact welding.
[0034] The welding tool 10 is inserted as follows while using the
method in accordance with the invention for the insertion of an
access port between a flexible foil and as second area-like
boundary part of a flexible container:
[0035] First, the access port made as a hose 4 is positioned
between the foil and the second boundary part. The welding tool 10
is then placed on from the side of the foil such that the
connection seam 2 to be established extends over the first surface
13 and the hose 4 is inserted along the groove 11, with the foil
extending between the groove 11 and the hose 4. The second surface
12 is chamfered toward the interior of the container in this case.
A correspondingly shaped counter-piece, not shown in any more
detail, provides a sufficient fixing from the side of the second
boundary part. If the second boundary part should likewise be made
as a flexible foil, a second welding tool 10 is expediently moved
to the second foil in a corresponding mirror-symmetrical manner.
The subsequent welding process along the heatable areas provides
the formation of a connection seam 2 which has a section as shown
in FIG. 2b.
[0036] The angle .alpha. can have an optimized value in dependence
on the application. It has been found to be particularly
advantageous for it to lie between 30 and 60 degrees (with a right
angle amounting to 90 degrees).
[0037] It is thus possible with the help of the invention to
substantially increase the stability of a flexible container in the
region of an access port, without this being accompanied by a
complex production technique or higher material costs. First trials
with a container in accordance with the invention have already
resulted in a clear improvement in fall strength. A material saving
can even be achieved with unchanged stability.
* * * * *