Note: Descriptions are shown in the official language in which they were submitted.
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De~criptios
The present invention refers to a foil bag of the type
explained in the generic clause of claim 1 and to a method
of filling such a foil ~ag.
Such a foil bag and a method of filling it are known from
German-Offenlegungsschrift 34 41 947. The known foil bag is
provlded with a filling hole, which is arranged in the upper
edge of the foil bag, slot-shaped and delimited by edges
consisting of the foil material. For the purpose of filling,
each of the lateral sealing seams is seized by a clamping
means. Subsequently, each o~ the upper foil edges has at-
tached thereto a suction means and is acted upon by a
vacuum. Following this, the suction means, which will
entrain the foil edges, are drawn apart, whereby the filling
hole will be spread open. It follows that the known foil bag
requires a compartively co~plicated filling system in the
case of which especially the vacuum pump used for producing
the suction pressure will increase the costs. In spite of
this fact, also the known system is unable to guarantee that
all bags can be opened reliably. If the foil edges adhere to
each other too strongly, it may happen that both foil edges
are dxawn towards one of the suction means. It is true that
attempts have already been made to counteract thls tendency .
by forming inside knobs in the area of the foil edges, but
this will make the production of the mass product foil bag
more expensive.
Hence, the present invention is based on the task of pro-
viding a foil bag whose filling hole can be opened simply
and without using complicated technical means.
This task is solved by the characterizing features of claim
1.
Due to the reinforcing element provided in accordance with
the present in~ention, the filling hole can be opened
reliably, without using any vacuum, in a purely mechanical
manner by pushing forces applied to the slot ends of the
filling hole, as de~cribed in claim 11. Complicated vacuum
means are no longer nece sary.
It is true that it has already been known to open flat
folding boxes in this way, but this will only function, if
the walls of these folding ~oxes are made of a sufEiciently
stiff material. If a pushing force were applied to the known
foil bag, both foil edges of khe filling hole would bulge to
the same side in the majority of cases. By providing the
reinforcing element according to the present invention, an
arrangement will, however, be obtained in the case of which
the pushing forces act precisely in the direction of the
510t and do not have any component which will cause bulging.
It follows that, by means of the reinforcing element pro-
vided in accordance with the present invention, it is also
possible to reliably open foil bags in the manner described
by applying a pushing force.
Advantageous further developments o~ the foil bag according
to the present inven~ion are described in claims Z to 10.
Claims 2 and 3 describe a particularly preferred arrangement
and structural embodimsnt of the reinforcing element and o
the filling hole.
on the basis of the measure according to claim 4, the
distribution and the introduction of the pushing force is
improved still further.
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In particular ln the case of comparatively long filling
holes, it will be expedient to provide one foil edge or both
foil edges with a bead according to claim 5; in this con-
nection, it will be expedient to provide the bead in the
middle of the respective foil edge in accordance with
claim 6.
The poin~ed-oval cross-section of the reinforcing element
disclosed in claim 7 will improve the introduction of the
pushing force on the one hand. On the other hand, such a
shape can be handled in a particularly expedient manner from
the point o~ view of production ~echnology, when the filling
hole and the reinforcing element are accommodated in the
upper edgs of the foil bag. In the case of this arrangement,
a gentle, fluid transition between the element and the foil
edges to be interconnected by welding is provided at the
tips of the pointed-oval cro~s-section so that the bag can
be closed without any risk of leaking holes.
In accordance with claims 8 and 9, the reinforcing element ~ :
can simultaneously fulfil the function of a discharge spout,
and it is not necessary to take any special me~sures for
this purpose.
On~ embodiment of the present invention will be explained in
detail hereinbelow on the basis of the drawings, in which
Fig. 1 shows a side view of the upper part of a foil bag
accor~ing to the invention,
Fig. 2 shows a top view of Fig. 1,
Fig. 3 shows a schematic representation of the foil bag
openlng process, and
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Fig. 4 shows a perspective view of the fully filled and
closed foil bag.
Fig. 1 and 2 show a foil bag 1 consisting of two plastic
foil blanks, one of which lies flat on top of the other,
said foil blanks being interconnected by comparati~ely broad
lateral sealing sea~s 2a, 2b. In th~-area o~ the bottom,
which is not shown in these figures, either a fold, or a
bott~ sealing seam, or the base surface outlined in Fiq. 4
can ~e provided. The ~oil blanks are rectangular, at least
in the upper area thereof, their upper sdge 2c ext~nding
from one lateral sealing seam 2a to the other lateral
sealing seam 2b. In the upper edge 2c of the foil bag 1, a
slot-shaped filling hole 3 is provided, which is delimited
by non-connected foil edges 3a, 3b of the upper edge 2c. The
filling hole 3 extend~ from one of the lateral sealing edges
2a up to and beyond the middle of the upper edge 2c. In the
middle of the filling hol~ 3, each of the foil edqes 3a, 3b
is Pm~ossed with a bead 4a, 4b, said beads defining an es-
sentially pointed-oval opening in the closed condition of
the filling hole 3.
Between the-filling hole 3 and the other lateral sealing
seam 2b, a r~inforcing element 5 is welded into the upper
edge_2c of the foil bag 1. The reinforcing element 5 is made
of plastic material and it has a symmetric, pointed- -
oval cross-seation (Fig. 2)o The lateral surface~ of the
reinforcing ele~ent 5, which are welded to the upper edge
2c, extend parallel so that they can precisely ba welded
into the upper edge 2c of khe foil bag 1. The rein~orcing
element 5 is oriented such that its two tips 5a, 5b are
located in line with the direction of the slot-shaped
filling hole 3, one of said tips 5a abutting on the filling
.
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hole 3 and the other tip 5b abutting on the lateral sPaling
edge 2b.
A discharge opening 6 extends through the r~inforcing ele-
ment 5, said discharge opening 6 ending outside o~ the bag 1
in a threaded spout 7, which is adapted to have attach~d
thereto an end cap 8 which can be screwed on. The rein-
forcing element can thus also be used as a discharge aid.
In the case of a ~oil ~ag 1 having a volumetric capacity of
approx. one litre and a width of approx. 160 mm, the fol-
lowing parameters proved to be particularly expedient:
width of the reinorcing element 5 in the direction of the
upper edge 2c: at least 60 mm,
width of the reinforcing element 5 transversely to the upper
edge 2c: not more than 16 mm,
width of the sealing seam 2a: 10 mm,
width of the beads 4a, 4b in the direction of the upper edge
2c: 10 mm,
length of the beads 4a, 4b from the upper edge 2b in the
direction of the bottom: at least 40 mm,
combination of materialso PET/PE 12/150 ~m,
stiffness: has to be determined in each individual case.
For the purpose of filling, the foil bag can be fixed in the
device, which is schematically outlined in Fig. 3. In said
device, each of the lateral sealing seams 2a, 2b is received
in an abutment 9a, 9b. Each of said abutments 9a, 9b is
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constructed as an angular trough, and the sealing seams 2a,
2b are adapted to b~ accurately positioned in the vertex of
said an~ular trough. The vertices of both abutments 9a, 9b
are positioned on a straight line, which extends through the
middle of the angular troughs. The abutments ga, 9b are
provided on co~pact, block-shaped components lOa, lOb, at
least one of said block-shaped components lOa, lOb being
adapted to be moved in the direction of the other block-
shaped component. ~s indicated by arrows A, a pushing force
acting in the direcction of the upper edge 2c is thus
exerted on the foil bag 1, said pushing force causing the
foil edges 3a, 3b to bulge in opposite directions - an
effect which is supported by ~he shape and arrangement of
the beads 4a, 4b, which has been chosen. In this way, th
filling hole is opened for inserting a filling head or for
directly filling in some type of filling material. In the
course of this process, the foil bag 1 can be held in posi-
tion by additional clamping means, which are well known in
the prior art, or the like. After the filling operation, the
abutments 9a, 9b are moved apart so that the foil bag 1 will
be relieved of the pushing force A. Due to the natural
flexibility of the material of the foil bag - if necessary
supported by clamping devices - the filling hole 3 will
close a~d will then be welded together by a sealing seam 11
in the conventional manner so that the shape shown in Fig. 4
will be obtained.
As a modification of the embodiment described and shown
hereinbefore, the slot-shaped filling hole can also be
arranged ak other locations of ~he foil bag, e.g. in one of
the lateral sealing seams or directly in the foil blank.
Furthermore, the use of the reinforcing element is not
limited to the essentially rectangular shape of the foil bag
shown in the drawings. The cross-sectional area of the re- ,-
inforcing element can be varied as long as it is guaranteed
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that its shape does not prevent the pushing forces from
being correctly introduced in the filling hole. If neces
sary, the width of the sealing seam abutting on the rein-
forcing element can be reduced to a normal width. Instead of
the trough-shaped abutments, it is also possible to use
oth~r suitable shapes; it would be expedient if these shapes
were of the self-centering type. It is also possible to
apply the pushing force by means of clamping devices, which
are adapted to be moved towards each other. For bags having
a deviating volumetric capacity andtor a d2viating width,
the width of the sealing seam and/or the dimensions of the
reinforcing element can be varied. If desired, reinforcing
elements can also be provided at both slot ends of the fil-
ling hole.
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