U.S. patent application number 12/208472 was filed with the patent office on 2009-03-19 for packaging bag with tearing aid.
Invention is credited to Martin GRIEBEL, Wolfgang Wittenbecher.
Application Number | 20090074333 12/208472 |
Document ID | / |
Family ID | 40348668 |
Filed Date | 2009-03-19 |
United States Patent
Application |
20090074333 |
Kind Code |
A1 |
GRIEBEL; Martin ; et
al. |
March 19, 2009 |
Packaging Bag with Tearing Aid
Abstract
The invention relates to a packaging bag with a tearing aid,
with which it is reliably provided that the packaging bag is opened
in a defined way by manual tearing by the user, so that no
packaging contents are lost. The packaging bag is essentially made
from a front and a back, which are connected to each other in their
edge regions with a material fit and which thus forms a joint edge,
in which an opening notch is formed, whose center line intersects
two weakened lines at an intersection point starting at a distance
from the notch tip. These weakened lines each extend across the
width of the front and the back. The direction of the weakened line
at the intersection point encloses, with the center line, a tear
angle greater than 0.degree. and less than 90.degree..
Inventors: |
GRIEBEL; Martin; (Jena,
DE) ; Wittenbecher; Wolfgang; (Gumperda, DE) |
Correspondence
Address: |
DUANE MORRIS LLP - NY;PATENT DEPARTMENT
1540 BROADWAY
NEW YORK
NY
10036-4086
US
|
Family ID: |
40348668 |
Appl. No.: |
12/208472 |
Filed: |
September 11, 2008 |
Current U.S.
Class: |
383/200 |
Current CPC
Class: |
B65D 75/008 20130101;
B65D 75/5805 20130101 |
Class at
Publication: |
383/200 |
International
Class: |
B65D 65/26 20060101
B65D065/26 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 18, 2007 |
DE |
10 2007 044 829.7 |
Claims
1. Packaging bag with tearing aid, comprising a front and a back,
said front and back being connected to each other at least
partially in their edge regions with a material fit thereby
defining a joint edge of a given edge width, an opening notch
formed in said joint edge, and two weakened lines which extend
across the width of the packaging bag defining a tearing region on
the front and the back and which divide the packaging bag into an
upper bag part and a lower bag part, wherein an extension of a
center line of said opening notch intersects said weakened lines at
an intersection point at a distance from the tip of said notch
outside of said notch forming a tear angle with said weakened lines
of greater than 0.degree. and less than 900.
2. Packaging bag according to claim 1, wherein said front and said
back have a rectangular form at least in said tearing region, and
said opening notch is formed on one of the side edges, and wherein
said center line of said opening notch extends perpendicular to a
side edge, and wherein the direction of the line layout of said
weakened lines at said intersection point encloses an angle greater
than 0.degree. and less than 90.degree. with said side edge.
3. Packaging bag according to claim 2, wherein the course of said
weakened lines represents an angled straight line.
4. Packaging bag according to claim 2, wherein the course of said
weakened lines is a sinusoid.
5. Packaging bag according to claim 1, wherein said front and said
back have a rectangular form at least in said tearing region,
wherein said opening notch is formed on one of the side edges of
said bag, and wherein said center line of said opening notch
extends at an angle greater than 0.degree. and less than 90.degree.
relative to said side edge, the course of said weakened lines is a
straight line.
6. Packaging bag according to claim 1, wherein said front and said
back have, at least in said tearing region, the shape of an
isosceles triangle, and said opening notch is formed on one of said
side edges of said bag, wherein said center line of said opening
notch extends perpendicular to a side edge, and the direction of
the course of said weakened lines at said intersection point
encloses, with said side edge, an angle greater than 0.degree. and
less than 90.degree..
7. Packaging bag according to claim 1, wherein said front and said
back have the shape of an isosceles triangle, at least in said
tearing region, and said opening notch is formed on one of the side
edges of said bag, wherein said center line of said opening notch
extends at an angle greater than 0.degree. and less than 90.degree.
relative to said side edge, and the course of the weakened lines is
a straight line.
8. Packaging bag according to claim 1, wherein said opening notch
is in the upper bag part.
9. Packaging bag according to claim 1, wherein said intersection
point lies within said joint edge.
10. Packaging bag according to claim 1, wherein said tear angle is
greater than 10.degree. and less than 45.degree..
11. Packaging bag according to claim 1, wherein said weakened line
is a lased line.
Description
FIELD OF THE INVENTION
[0001] The invention relates to a packaging bag made from a
flexible one-layer or multi-layer packaging material, such as,
paper, plastic, and/or metal, with a tearing aid that allows
defined tearing of the packaging bag.
BACKGROUND OF THE INVENTION
[0002] The necessity of defined tearing of a packaging bag, when
such a bag is opened by manual tearing without the use of any tool,
is especially important if the package contents involve such
materials as liquid, bulk material, or a plurality of small parts,
so that the packaging contents partially or completely escape as a
result of uncontrolled opening of the packaging bag.
[0003] The packaging size and the packaging material of packaging
bags according to the class are defined as a function of the type
and quantity of the package contents and can be very different.
These packaging bags can indeed differ in shape, but, in the
broadest sense, they always involve a packaging bag with a front
and a back, which are connected to each other in their edge region
with a material fit. The connection can already exist over a part
of the edge region due to a folding of the blank for the packaging
bag. The other parts of the edge region are connected to each other
by adhesion or fusion over a given edge width (called joint edge
below).
[0004] Upon vertical positioning or holding of the packaging bag,
for which the labeling on the packaging bag contains adequate
instruction, a hollow space forms in the upper region of the bag
volume free of the packaging contents. In this region, the front
and the back can be at least partially brought into contact with
each other when they are pressed together. So that no packaging
contents are lost as the package is being torn, the tear line that
is being formed, starting from the edge region bordering the hollow
space, may extend only across the regions of the front and back
that border the hollow space. However, without a tearing aid, most
materials do not always tear in the desired regions.
[0005] Examples for packaging bags according to the invention will
be discussed below.
[0006] For packaging building materials, such as cement, frequently
a two-layer packaging material is used that consists of a plastic
film, which faces the interior of the bag and which serves the
purpose of merely protecting the packaging contents from moisture,
and a very tear-resistant, robust paper layer that faces the
exterior of the bag and which reliably withstands both the weight
of the packaging contents itself, which, in the case of cement, can
exceed 30 kg, and the transport loads. The bag shape here is a
typical sack shape defined by an upper edge, a lower edge, and two
side edges. The side edges, and often the lower edge, are formed
here by means of creases. The upper edge is a joint edge with a
typical edge width of ca. 1-4 cm.
[0007] Rather than weight, but instead requirements for hygiene and
long storage life for the packaging contents are important for
packages in the food and beverage industry. Particularly for
beverage packages, three-layer packaging materials are used
consisting of an outer, printed paper or plastic layer, a metal
layer, and an inner plastic layer. Here, the typically rectangular
bag shapes are often bonded or fused to each other along all of the
edges, i.e., the packages have a peripheral joint edge, with a
typical edge width of about 2-8 mm.
[0008] The packaging material for such items as individually
packaged sweets is often only a single-layer plastic film, which is
produced, for example, as a tube and which has a lower and an upper
joint edge.
[0009] In principle, the packaging material is produced in webs or
sheets and finished into individual blanks. The blanks are then
folded or preformed, and edges lying one on top of another are
fused or bonded to each other so that a packaging bag is formed
that is completely closed after being filled.
[0010] A joint edge is always produced, so that the packaging
materials lying directly one on another are connected to each other
across a given edge width. The joint edge can be a peripheral,
closed edge or can be interrupted by creases.
[0011] Packaging bags that have an I-shaped or V-shaped opening
notch in a lateral joint edge are widely known. Then, for opening,
the packaging bag can be gripped at the joint edge on both sides of
the opening notch and pulled apart. The tear is started in the
notch direction and should progress through the packaging material
in the notch direction, which, however, does not happen in practice
if the tear is not guided in this direction.
[0012] From practice, solutions are also known in which weakened
lines are formed across the width of the front and/or back of the
packaging bag, whereby a tear progression is indeed guided, but
there is the difficulty of starting the tear at the beginning of
the weakened line.
[0013] The introduction of an opening notch and a weakened line,
which opens into the end of the opening notch, appears to bring
together the advantages of both alternatives currently known from
past practice. However, to implement this in industrial mass
production is very difficult technically, because the two cannot
take place in one process, where the opening notch must be
positioned exactly relative to the weakened line.
[0014] No solutions have been presented that combine an opening
notch in the edge region and a weakened line running across the
width of a packaging bag.
[0015] The formation of a weakened line can take place, in
practice, only before the folding or shaping of the packaging bag.
Ideally, it is formed into the material web before it is
partitioned into blanks for the packaging bag.
[0016] The weakened lines can be a partial material separation, a
partial material removal, or also embossing along the line course
of the desired weakened line.
[0017] A partial material separation can be a deep cut that does
not completely separate the material, for example, produced with a
knife or a stamp.
[0018] A partial material removal can be an incomplete separating
groove or a perforation or slit line of partially or completely
penetrating perforations or slots, or combinations of these.
[0019] The formation of an opening notch, in practice, can only be
made after the fusing or adhesion of the edge regions. Here, the
depth of the notch may not be greater than the width edge of the
formed joint edge. To fulfill the mentioned requirements, this
processing step must be controlled as a function of the position of
the weakened line. Means must be provided that detect the position
of the weakened line, in order to control signals that can be
derived from these means as control parameters for the positioning
of the packaging bag relative to the processing tool for the
opening notch, which would be very complicated.
SUMMARY OF THE INVENTION
[0020] The invention is based on the problem of creating a
packaging bag with a front and a back connected by a joint edge, in
which, for guiding a tear, an opening notch and weakened lines are
formed for guided tear progression.
[0021] This problem is solved by a packaging bag with the features
set forth in claim 1.
[0022] Advantageous improvements are described in the subordinate
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Examples of a packaging bag according to the present
invention will be described in more detail below in connection with
the annexed drawings, in which:
[0024] FIG. 1a shows a first embodiment in top view;
[0025] FIG. 1b shows a material web with the blank for the first
embodiment;
[0026] FIG. 1c shows a cutout from FIG. 1a;
[0027] FIG. 2 shows a second embodiment;
[0028] FIG. 3 shows a third embodiment;
[0029] FIG. 4 shows a fourth embodiment;
[0030] FIG. 5 shows a fifth embodiment;
[0031] FIG. 6 shows a sixth embodiment;
[0032] FIG. 7 shows a seventh embodiment;
[0033] FIG. 8 shows a packaging bag with triangular front and
back;
[0034] FIG. 9 shows a packaging bag with additional base part;
and
[0035] FIG. 10 shows a packaging bag with different front and back
sides.
DESCRIPTION OF AN EMBODIMENT OF THE INVENTION
[0036] As is known from practice, packaging bags according to the
invention have a front 1 and a back 2, which are at least partially
fused or bonded to each other in their edge regions. The edge
regions bonded or fused to each other form joint edges 3 of a
predetermined edge width.
[0037] In FIG. 1a, a first embodiment of a packaging bag according
to the invention is shown in top plan view onto the front 1. The
front 1 and the back 2, lying behind the front, have a rectangular
shape and are connected to each other by means of a peripheral
joint edge 3.
[0038] A blank 4 for this packaging bag, shown in FIG. 1b, is
advantageously cut to length from a web of packaging material and
has twice the width of the packaging bag. Through folding along the
center line, the front 1 and the back 2 are placed so that one
overlaps the other. The crease formed by the fold forms one of the
two side edges. Connecting the other side edge and the bottom edge
would be sufficient to create a packaging bag that can be filled.
To achieve an overall symmetric impression or to be able to
adequately grip the packaging bag peripherally, however, as a rule
the edge region along the crease is also formed as a joint edge
3.
[0039] It is clear to someone skilled in the art that the blank 4
can also be shaped in such a way that the front 1 and the back 2
can overlap by means of the bottom edge or also the upper edge. In
the latter variant, filling would then be performed from below.
[0040] The shape of the two sides need not necessarily be
rectangular or identical. For example, in addition to FIGS. 1 to 7,
in which the shape of the packaging bag is rectangular, at least in
the tear region, FIG. 8 shows a packaging bag with two identical
triangular side surfaces, FIG. 9 shows a packaging bag with two
identical trapezoidal side surfaces and a third round surface
forming a base. In a packaging bag according to FIG. 10, the front
side is trapezoidal, and the back is rectangular. A third surface
forming a base creates the equalization for the edges of different
lengths of the front and the back.
[0041] All of the embodiments for a packaging bag according to the
invention have the following in common:
[0042] an opening notch 5 is provided in a joint edge 3;
[0043] two weakened lines 6 are provided across the width of the
packaging bag, more precisely, the front 1 and the back 2, wherein
these weakened lines 6 divide the packaging bag into an upper bag
part 9 and a lower bag part 10; and
[0044] the center line 7 of the opening notch 5 intersects the
weakened lines 6 at an intersection point 8 at an angle greater
than 0.degree. and less than 90.degree. (referred to herein as tear
angle .alpha.) outside of the opening notch 5 at a distance "a"
from the notch tip.
[0045] The combination of an opening notch 5 with weakened lines 6
in the manner described represents a tearing aid and is essential
to the invention.
[0046] A special advantage of this tearing aid lies in its simple
production.
[0047] It is technically simple to produce an opening notch 5 and
the weakened lines 6 with the given conditions because the
introduction of the opening notch 5 need not be oriented exactly to
the position of the already given weakened lines 6. In particular,
if the opening notch 5 is located in the upper bag part 10, it can
deviate considerably from its desired position relative to the
weakened line 6, without this having significant effects on the
tear behavior. In FIG. 8, examples of permissible position
deviations are shown.
[0048] By spreading apart the regions bordering the opening notch
5, as known from practice, a tear is introduced by means of the
notch tip. The tear propagates from the notch tip in an
uncontrolled way in the front 1 and the back 2 of the packaging bag
until it meets the weakened lines 6 at an intersection point 8.
Strictly speaking, as it leaves the joint edge 3, i.e., at the end
of the material connection between the front 1 and the back 2, the
spreading tear divides into two tears. Because they spread in an
uncontrolled way, they could also meet the weakened lines 6 at
different intersection points 8. However, in order not to
unnecessarily complicate the description of the invention, only one
tear is referred to below, which, starting from the notch tip,
meets the weakened lines 6 at an intersection point 8.
[0049] From there, the progression of the tear is guided along the
weakened lines 6, that is, the packaging bag is separated in a
defined way into a lower bag part 9 and an upper bag part 10, apart
from a negligibly short path. The separation line defines the
opening edge of the lower bag part 9 that is formed. Through a
selected guidance of the weakened lines 6, which form the
separation line, the opening edge can be advantageously formed for
discharging or pouring out the packaging contents.
[0050] The weakened lines 6 need not be identical in their line
course on the front 1 and on the back 2. Also, the distance "a" and
the intersection point 8 need not be identical, relative to the
front 1 or the back 2. However, in order not to unnecessarily
complicate the description of the invention, a congruent line
layout shall be assumed, which has the same spacing "a" and the
same intersection point 8 on the front 1 and the back 2. An
identical line layout is advantageous for the tear behavior,
because both weakened lines 6 should be separated simultaneously
under the action of a tear force.
[0051] Certain advantageous parameter variations of a packaging bag
according to the invention are discussed hereinbelow.
[0052] Essentially, the positioning of the opening notch 5, the
opening angle, and the depth of the opening notch 5, the line
layout of the weakened line 6, and its formation, the tear angle
.alpha. and the distance "a" can vary.
[0053] The opening angle of the opening notch 5 has significance
only insofar as the opening notch 5 can be better visually detected
with a larger opening angle. For fulfilling its function, the
opening notch 5 can also be limited to a narrow slot.
[0054] The depth of the opening notch 5 must be selected so that
the notch tip still lies completely in the joint edge 3. For an
opening notch 5 whose center line 7 meets the edge of the joint
edge 3 at a right angle, this means that the depth of the opening
notch 5 is smaller than the edge width of the joint edge 3. The
opening notch 5, however, is at least deep enough that the
packaging material can be separated by a moderate tearing force up
to the intersection point 8 with the weakened lines 6.
[0055] For the tearing behavior, the tear angle .alpha. should be
as small as possible. Indeed, the reliability of the tear
intersecting the weakened lines 6 increases when the tear angle
.alpha. is larger, but for a small tear angle .alpha., the
component of the tearing force in the direction of the weakened
line 6 increases as the tear angle .alpha. decreases. Preferably,
the tear angle .alpha. should therefore be greater than 10.degree.
and less than 45.degree..
[0056] The distance "a" should be as small as possible. However, if
it is selected too small, then position deviations of the opening
notch 5 from its desired position could have the effect that the
center line 7 intersects the desired line in the opening notch 5. A
tear propagating from the notch tip would then not intersect the
weakened lines 6.
[0057] The weakened lines 6 can be produced by any known material
attenuation that can be realized along a line. In particular, the
weakened line 6 can be [0058] a continuous cut line with a constant
or variable depth of cut, [0059] a line of slits or perforations or
combinations of these, which are separated by connecting pieces and
penetrate or do not penetrate the material, [0060] a stamped line,
or [0061] a line along which the packaging material has different
material properties.
[0062] In FIGS. 1-10, the weakened lines 6 are each shown as dashed
lines, which represent all of the mentioned embodiments.
[0063] As tools for production, typical tools for material
separation, material removal, or material modification can be
used.
[0064] A laser appears to be especially well suited. The
possibilities in the selection of a laser with a wavelength
suitable for the corresponding packaging material, the adaptation
of the laser parameters to the desired material attenuation, and
also the variable controllability of the laser radiation, such as,
by means of a robot arm or a scanner, make a laser the tool of
choice and a lased weakened line a preferred implementation of a
weakened line 6.
[0065] The weakened lines 6 divide the packaging bag into a lower
bag part 9 and an upper bag part 10. When the packaging bag is
completely torn, the upper bag part 10 is separated from the lower
bag part 9, and the packaging contents should be located completely
in the lower bag part 9.
[0066] The line course of the weakened lines 6 is preferably
straight, angled, or curved, wherein changes in direction should be
as continuous as possible.
[0067] In the first embodiment of a packaging bag shown in FIGS.
1a-1c, the weakened lines 6 have an angled line layout, and these
weakened lines correspond to the three edges of the peripheral line
of an isosceles trapezoid. The opening notch 5 is formed in the
joint edge 3 bordering a side edge, wherein the center line 7 is at
a right angle to the side edge. At the intersection point 8, the
direction of the line course of the weakened lines 6 encloses, with
the side edge and thus also the center line 7, a tear angle .alpha.
of greater than 0.degree. and less than 90.degree., ca. 45.degree.
here, for example. The distance "a" is selected so that a tear
introduced via the opening notch 5 intersects the weakened lines 6
outside of the joint edge 3. If the distance "a" is selected to be
too large, then there is the risk that the progressing tear will
spread in an uncontrolled way into the lower bag part 9 and, thus,
a defined opening would no longer be possible, even before it
intersects the weakened lines 6.
[0068] In a second embodiment shown in FIG. 2, the distance "a" is
reduced in order to increase the reliability that an introduced
tear actually intersects the weakened lines 6 and does not run away
from these lines in an uncontrolled way. The intersection point 8
still lies within the joint edge 3. This has the effect that the
guidance of the progressing tear still starts within the joint edge
3. Instead of an abrupt change in direction according to FIG. 1a,
the line layout of the weakened line 6 has a continuous change in
angle, due to the rounding of the angled line layout.
[0069] Like all of the embodiments described below, the third
embodiment shown in FIG. 3 differs from the two aforementioned
embodiments in that the opening notch 5 is not formed within the
lower bag part 9, but instead within the upper bag part 10.
[0070] This has the advantage that a tear that progresses from the
notch tip of the opening notch 5 intersects each of weakened lines
6 completely independently of the distance a.
[0071] In this third embodiment, the lateral edge regions are not
formed as a joint edge 3, but instead are delimited exclusively by
creases. Here, the packaging bag is closed across its length, as
shown, on the back 2. The opening notch 5 is located in the joint
edge 3 bordering the upper edge of the packaging bag.
[0072] The fourth embodiment, shown in FIG. 4, has a sinusoidal
line course of the weakened lines 6. Therefore, the open edge of
the lower bag part 9 (bag opening) is constructed in such a way
that the valley of the sinusoid forms a spout in the front 1 and
the back 2. Because the spouts are not exactly opposite in the
periphery of the bag opening, liquid packaging contents will be
emptied exclusively through one of the spouts, as long as it is
held at the lowest point.
[0073] In the fifth embodiment shown in FIG. 5, the line course of
the weakened lines 6 is again a sinusoid, which is shifted by a
half period relative to that in FIG. 4, so that the weakened lines
6 taper off into a valley at the side edges. Here, the valleys
could also be used as spouts, in particular, the one opposite the
opening notch 5. The opening notch 5 is here formed again in the
joint edge 3, bordering a side edge, and is nevertheless located in
the upper bag part 10.
[0074] Such a construction appears to be especially advantageous
because, by means of the opening notch 5 in the upper bag part 9,
it is assured that the tear will intersect the weakened line 6,
that the packaging contents can be easily emptied and that the user
can tear the packaging bag in the usual way, starting from one side
edge.
[0075] The advantage of a sinusoidal line layout or another
periodic line layout also lies in its simple realizability, such
as, by means of a laser scanner.
[0076] In FIGS. 6, 7, and 8, embodiments are shown in which the
line layout of the weakened lines 6 corresponds to a straight line.
So that the weakened lines 6 and the center line 7 of the opening
notch 5 nevertheless intersect each other at a tear angle .alpha.,
the opening notch 5 in the sixth embodiment shown in FIG. 6 is
formed at a corner, wherein the joint edge 3 limited here would
have a wider construction.
[0077] In the seventh embodiment disclosed in FIG. 7, the opening
notch 5 would be formed at an angle to the side edge, i.e., the
center line 7 is not perpendicular to the side edge.
[0078] In the embodiment shown in FIG. 8, as already explained, the
front 1 and the back 2 are triangular surfaces, which is why an
opening notch 5 formed perpendicular to the side edge intersects a
straight weakened line 6 running across the width of the packaging
bag at a tear angle .alpha.. In such a solution, the tear angle
.alpha.. equals the vertex angle of the triangle, here 35.degree..
Alternative locations for the opening notch are shown at (5).
[0079] The smaller the tear angle .alpha., the more easily the tear
can transition into the weakened line 6.
[0080] List of reference symbols [0081] 1 Front [0082] 2 Back
[0083] 3 Joint edge [0084] 4 Blank [0085] 5 Opening notch [0086] 6
Weakened line [0087] 7 Center line of the opening notch [0088] 8
Intersection point [0089] 9 Lower bag part [0090] 10 Upper bag part
[0091] .alpha. Tear angle [0092] a Distance
[0093] While the invention has been illustrated and described in
connection with currently preferred embodiments shown and described
in detail, it is not intended to be limited to the details shown
since various modifications and structural changes may be made
without departing in any way from the spirit of the present
invention. The embodiments were chosen and described in order to
best explain the principles of the invention and practical
application to thereby enable a person skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated.
* * * * *