U.S. patent application number 11/764730 was filed with the patent office on 2007-10-11 for easy opening rear seam bags and packaging methods.
Invention is credited to Randy R. McKellar.
Application Number | 20070237434 11/764730 |
Document ID | / |
Family ID | 36578409 |
Filed Date | 2007-10-11 |
United States Patent
Application |
20070237434 |
Kind Code |
A1 |
McKellar; Randy R. |
October 11, 2007 |
EASY OPENING REAR SEAM BAGS AND PACKAGING METHODS
Abstract
A package bag may be made from a sheet of flexible packaging
material that has been folded along a longitudinal direction with
the edges of the sheet brought together and sealed to form a
longitudinal rear seam. A starter cut has been formed only in the
longitudinal seam to facilitate opening the package bag. The
package bag may be opened by pulling in opposite directions on the
longitudinal seam at points on either side of the starter cut. Such
package bags may be made from a sheet of flexible roll stock having
one or more notches formed at spaced apart locations along one or
more edges of the sheet. When the sheet is folded such that the
edges meet and are sealed to form a longitudinal rear seam of a
package bag, the notches provide a starter cut for opening the
package bag.
Inventors: |
McKellar; Randy R.;
(Hayward, CA) |
Correspondence
Address: |
JOSHUA D. ISENBERG;JDI PATENT
809 CORPORATE WAY
FREMONT
CA
94539
US
|
Family ID: |
36578409 |
Appl. No.: |
11/764730 |
Filed: |
June 18, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11009183 |
Dec 10, 2004 |
|
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11764730 |
Jun 18, 2007 |
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Current U.S.
Class: |
383/200 ;
383/120 |
Current CPC
Class: |
B65B 9/20 20130101; B65B
61/18 20130101; B65B 61/02 20130101; B65D 75/5827 20130101 |
Class at
Publication: |
383/200 ;
383/120 |
International
Class: |
B65D 33/00 20060101
B65D033/00 |
Claims
1. A composition of matter for forming a package bag, comprising: a
sheet of flexible roll stock having one or more notches formed at
spaced apart locations along one or more edges of the sheet,
wherein, when the sheet is folded such that the edges meet and are
sealed to form a longitudinal rear seam, the notches provide a
starter cut only in the rear seam for opening package bags formed
from the sheet of flexible roll stock.
2. The composition of matter of claim 1 wherein the one or more
notches are formed along a single edge of the sheet.
3. The composition of matter of claim 1 wherein the one or more
notches are formed in two edges of the sheet.
4. The composition of matter of claim 1 wherein the one or more
notches include one or more pairs of aligned notches that overlap
at least partially when the sheet is folded such that the edges
meet.
5. The composition of matter of claim 1, further comprising one or
more guide strips formed onto the sheet of roll stock, wherein the
guide strips run laterally across the sheet proximate the one or
more notches.
6. The composition of claim 1 wherein the one or more guide strips
include pairs of two closely-spaced guide strips disposed such that
the starter cut lies between the two guide strips.
7. A packaging method, comprising the steps of: folding a sheet of
flexible packaging material along a longitudinal direction first to
bring first and second edges of the sheet together; sealing the
first and second edges to form a longitudinal rear seam along the
longitudinal direction; and forming a starting cut only in the
longitudinal seam to facilitate opening the package bag
8. The method of claim 7 wherein forming the starter cut includes,
before folding the sheet of flexible packaging material, forming
one or more notches in the sheet of flexible packaging material at
spaced apart locations along one or more edges of the sheet,
wherein, when the sheet is folded to bring the first and second
edges together and are sealed to form the longitudinal seam, the
notches provide the starter cut.
9. The method of claim 7, further comprising the step of forming
one or more guide strips onto the sheet of flexible packaging
material, wherein the guide strips run laterally across the sheet
proximate the starter cut.
10. The method of claim 9, wherein the one or more guide strips
include two closely spaced guide strips disposed such that the
starter cut lies between the two guide strips.
11. The method of claim 7, further comprising the step of, after
folding the sheet of flexible packaging material, sealing a first
end of the folded sheet to close a first end of a bag.
12. The method of claim 11 wherein the starter cut is formed before
sealing the first end of the folded sheet.
13. The method of claim 11, further comprising the step of, after
sealing the first end of the folded sheet to close the first end of
the bag, filling the bag with one or more products.
14. The method of claim 13 further comprising, the step of, after
filling the bag with one or more products, sealing a second end of
the folded sheet to close a second end of the bag.
15. The method of claim 13 wherein forming the starter cut takes
place before sealing the second end of the sheet or before filling
the bag.
16. The method of claim 7, wherein the sheet of flexible packaging
material comprises a sheet of flexible roll stock having one or
more notches formed at spaced apart locations along one or more
edges of the sheet, wherein, when the sheet is folded such that the
edges meet and are sealed to form the longitudinal rear seam, the
notches form the starter cut.
17. The method of claim 16 wherein the one or more notches include
one or more pairs of aligned notches that overlap at least
partially when the sheet is folded such that the edges meet.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional patent application of and
claims the benefit of priority of co-pending U.S. patent
application Ser. No. 11/009,183, entitled "EASY OPENING REAR SEAM
BAGS AND PACKAGING METHODS", filed Dec. 10, 2004, the entire
disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to packaging and more particularly to
easy open bags and methods of manufacturing such bags.
BACKGROUND OF THE INVENTION
[0003] Modern packaging for food and other products often uses
sealed bags having seams at one or more ends of the bag and an
exposed seam that usually runs the entire length of the rear of the
bag. Such bags have been conventionally made of a packaging
material, such as a synthetic resin film or a laminated material
formed by laminating the synthetic resin film and an aluminum foil
or the like. The package bag is filled with a material to be
packed, such as liquids, powders or viscous materials, before being
hermetically sealed.
[0004] To open the package bag, therefore, it is common practice
for a user of the products stored in the bag to cut a sealed
portion of the package film as the packaging material with a knife
or scissors or break it open with a fingertip. When the package bag
is to be cut with a knife or scissors, the opening procedure is
troublesome, as it requires a tool. When the package film is to be
ruptured with a fingertip, the opening of the package film may not
be accomplished easily. Unfortunately, the material from which
these bags are made and the sealing of the seams can make the bag
difficult to open.
[0005] There have been several attempts in the prior art to address
the problem of opening sealed package bags. For example, U.S. Pat.
No. 6,352,364 issued Mar. 5, 2002 to Mobs starts a tear on the side
of the bag and then has the longitudinal seal cut to ease the tear
through it. This requires that two cuts be aligned and also
requires modification of the end seal.
[0006] Similarly, U.S. Pat. No. 6,343,876 issued Feb. 5, 2002 to
Takahashi et al describes starting the tear on the side of a pouch
that has seams running down each side and no rear seam.
[0007] U.S. Pat. No. 6,102,571 issued Aug. 15, 2000 to Moteki et al
also initiates the tear from the side of the bag then has a second
tear-able zone for tearing through the rear seam.
[0008] U.S. Pat. No. 5,371,997 issued Dec. 13, 1994 to Kopp et al
describes a long and narrow bag with a longitudinal seam on one
side of the bag with the tear being initiated from the side of the
bag.
[0009] U.S. Pat. No. 5,067,306 issued Nov. 26, 1991 to Umezawa
describes making micro cuts on the sides of the bag material as it
is being packaged, but makes no mention of the problem tearing
through the rear seam of the bag.
[0010] U.S. Pat. No. 4,725,329 issued Feb. 16, 1998 to Tani it uses
a tear string to tear through the rear seam of a package bag.
However, a tear string could be hard to manage on large bags like
potato chips.
[0011] Thus, there is a need in the art, for an easy opening
package bag and a method for manufacturing it.
SUMMARY OF THE INVENTION
[0012] According to an embodiment of the invention, a package bag
may be made from a sheet of flexible packaging material that has
been folded along a longitudinal direction with the edges of the
sheet brought together and sealed to form a longitudinal rear seam.
A starter cut is formed only in the rear seam to facilitate opening
the package bag. The package bag may be opened by pulling in
opposite directions on the longitudinal seam at points on either
side of the starter cut.
[0013] According to another embodiment of the invention a
composition of matter is provided for forming a package bag. This
composition of matter includes a sheet of flexible roll stock
having one or more notches formed at spaced apart locations along
one or more edges of the sheet. When the sheet is folded such that
the edges meet and are sealed to form a longitudinal rear seam, the
notches provide a starter cut only in the rear seam for opening
package bags formed from the sheet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The teachings of the present invention can be readily
understood by considering the following detailed description in
conjunction with the accompanying drawings, in which:
[0015] FIGS. 1A-1C are three-dimensional diagram of package bags
according to an embodiment of the present invention;
[0016] FIG. 2 is a three-dimensional schematic diagram illustrating
the manufacture and filling of bags according to another
alternative embodiment of the present invention.
[0017] FIGS. 3A-3B are three-dimensional diagrams of rolls of
material for forming a package bags according to an alternative
embodiment of the present invention; and
[0018] FIG. 4 is a three-dimensional schematic diagram illustrating
the manufacture and filling of bags according to another
alternative embodiment of the present invention.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0019] Although the following detailed description contains many
specific details for the purposes of illustration, anyone of
ordinary skill in the art will appreciate that many variations and
alterations to the following details are within the scope of the
invention. Accordingly, the exemplary embodiments of the invention
described below are set forth without any loss of generality to,
and without imposing limitations upon, the claimed invention.
[0020] FIG. 1A depicts a package bag 100 according to an embodiment
of the present invention. The bag depicted in FIG. 1A is a
relatively simple type of bag known as a pillow bag or pillow
pouch. The bag 100 is generally made from a sheet of flexible
packaging material that has been folded along a longitudinal
direction. The side edges of the sheet have been brought together
and sealed to form a longitudinal rear seam 102 disposed between
the sides of the bag. A starter cut 104 has been formed in the rear
seam 102 to facilitate opening the package bag. End seams 106, 108
close the ends of the package bag 100 to seal products within it.
As a result of the starter cut 104, the package bag 100 may be
opened by pulling in opposite directions on the longitudinal seam
at points on either side of the starter cut.
[0021] The rear seam 102 usually lies flat against the package bag
100 but can easily be lifted to provide finger grab points on both
sides of the starter cut 104. Embodiments of the present invention
work with any bag that has a seam that can be lifted from the bag.
During manufacturing of the bag the rear seam 102 may be formed
perpendicular to the rear surface of the bag and then folded over
to lay flat against the bag. This makes it very handy to pull the
seam up and use it to provide finger grab points for tearing the
bag open.
[0022] In some embodiments, one or more guide strips 105, 107 are
placed laterally across the package bag near the starter cut 104 to
guide the tear that results when the rear seam 102 is pulled. The
guide strips are made of tear-resistant material, such as plastic
that are formed onto or into the material of the bag 100. A single
guide strip may be used or, as shown in FIG. 1A, two guide strips
may be placed close together on either side of the starter cut to
contain the tear between the two guide strips.
[0023] Embodiments of the present invention may be used with other
types of bags having a longitudinal rear seam. Examples of such
bags include a gusseted bag 110 and a flat bottom bag 120,
respectively depicted in FIG. 1B and FIG. 1C. The gusseted bag 110
includes a rear longitudinal seam 112, starter cut 114 and end
seams 116, 118 and special folds or gussets that give the bag a
substantially rectangular cross-section. The flat bottom bag 120
includes a rear longitudinal seam 122 and starter cut 124 an end
seal 126 and folds and seals that provide both a rectangular cross
section and a flat bottom 128. Such package bags are well known
within the packaging arts. Guide strips, such as those described
above, may also be used with the gusseted bag 110 and/or the flat
bottom bag 120.
[0024] Package bags of the type described herein may be used to
store any type of products commonly stored in sealed bags. Such
products include, but are not limited to snacks, such as potato
chips and pretzels, coffee, cheese, produce, candy, frozen foods,
sealed medical products such as bandages, tape medicine, detergent,
chemical powders, cosmetics among many others.
[0025] Package bags of the type described herein can be fabricated
by a number of different techniques. Products are often packaged in
bags using vertical form-fill machines or horizontal form-fill
machines. Such machines form the bags from a continuous sheet of
roll stock and fill them as the bags are fabricated. FIG. 2
illustrates one example, among others, of a technique for packaging
products in bags of the type described above. In this example, a
vertical form-fill system 200 forms the bags from a sheet of
material 202. The sheet may made of any suitable flexible material
used in the packaging industry, examples of which include, but are
not limited to, polyethylene (e.g. low density polyethylene (LDPE)
or linear low density polyethylene (LLDPE), polypropylene,
metallocene or laminated film. Examples of suitable laminated films
include polyester/poly, paper/poly, glassine/poly, Bopp/foil/poly
and the like. The sheet 202 may be in the form of a roll stock,
e.g., a laminated film roll stock or surface printed roll stock.
Materials for making bags are available, e.g., from Duralam, Inc.
of Appleton, Wis. and other commercial suppliers.
[0026] The sheet 202 is drawn from a roll 204 over a series of
rollers to a vertical form-fill tube 206. The sheet 202 wraps
around the form-fill tube 206 and the edges of the sheet 202 are
brought together to form the sheet 202 into a tube. A longitudinal
sealer device 207 seals the edges of the sheet 202 together to form
the rear seam 208 of a bag 210. An end sealer then seals one end of
the bag 210. Typically the edges and ends are sealed by some
combination of heat and pressure. After the end is sealed the bag
210 is filled through the form-fill tube 206. Then the second end
is sealed to close the bag 210. A shearing device 212 cuts the
sheet 202 along the end seal to separate the bag from subsequent
bag that is formed from the same sheet material 202. The shearing
device 212 may leave part of the end seal on the bag 210 and part
on the subsequent bag.
[0027] The starter cut described above can be made in the rear seam
at any point in this procedure. For example a notch-cutting device
214, e.g., a sliding knife can cut a notch 215 in the rear seam 208
to form the starter cut. In FIG. 2, the notch-cutting device 214 is
located between the longitudinal sealer device 207 and the shearing
device 212. Alternatively, the notch-cutting device may be located
after the shearing device 212 or at some other convenient point in
the system 200.
[0028] In an alternative embodiment, the starter cut may be made as
part of the production of the roll stock used to form the bags.
This is particularly advantageous in that such a roll stock can be
used in an existing form-fill machine without having to modify the
machine to make the starter cut in the rear seam. FIG. 3A depicts
an example of a sheet of material 300 for forming bags that can be
used to make package bags according to an embodiment of the present
invention. The material 300, e.g., any of the flexible materials
described above, may be in the form of a sheet 302 of flexible roll
stock which may be wound into a roll 304 suitable for use in a
form-fill machine. The sheet 302 has first and second surfaces 301,
303. One surface 301 typically has no printing and serves as the
inside of a bag. The other surface 303, which may have printing on
it, serves as the outside of the bag. The printing may be done by
conventional equipment, such as that provided by Paper Converting
Machine Company of Green Bay Wis. The sheet is cut along lines
indicated by D during forming and filling to separate individual
bags from the sheet 302. The sheet 302 may or may not be perforated
along the lines D to facilitate separate of the bags.
[0029] One or more notches 306 are formed at spaced apart locations
along one or more edges 308 of the sheet 302. When the sheet 302 is
folded such that the edges 308 meet and are sealed to form a
longitudinal rear seam, the notches 306 provide a starter cut for
opening package bags formed from the sheet 302. In some embodiments
a single notch is formed along one edge. In other embodiments,
aligned notches 306 are formed in both edges 308 of the sheet 302.
The aligned notches 306 overlap at least partially to form a
starter cut all the way through the rear seam.
[0030] FIG. 3B depicts a material 310 that is a variation on the
material 300 of FIG. 3A. The material 310 may be in the form of a
sheet 312 and may be wound into a roll 314. The sheet 312 may be
made from any suitable flexible bag-making material. The sheet 312
includes guide strips 318 formed laterally across the sheet
proximate notches 316. In the example depicted in FIG. 3B pairs of
guide strips 318 are placed close together with a notch 316 between
the two guide strips in each pair. Alternatively a single guide
strip may be placed such that the notches lie between a guide strip
and a location D where the sheet 312 is to be cut to separate one
bag from another.
[0031] FIG. 4 illustrates one example, among others, of a technique
for packaging products in bags of the type described above using
the pre-notched roll stock of the types described in FIGS. 3A-3B.
In this example, a vertical form-fill system 400 forms the bags
from a sheet of material 402. By way of example, the system 400 may
be a Model VPK vertical/form/fill machine from Rovema Packaging USA
of Lawrenceville, Ga. In this case, the sheet 402 already has
notches 403 in its edges as described above with respect to FIG. 3A
as well as lateral guide strips 405 as described above with respect
to FIG. 3B. The sheet 402 is drawn from a roll 404 over a series of
rollers to a vertical form-fill tube 406. The sheet 402 wraps
around the form-fill tube 406 and the edges of the sheet 402 are
brought together to form the sheet 402 into a tube. The notches on
opposite edges of the sheet 402 align and overlap to form the start
cut 401. A longitudinal sealer device 407 seals the edges of the
sheet 402 together to form the rear seam 408 of a bag 410. An end
sealer then seals one end of the bag 410 along the line indicated
at D, the bag is filled through the form-fill tube 406 and the
second end is sealed to close the bag 410. A shearing device 412
may cut the sheet 402 along the end seal to separate the bag from
subsequent bag that is formed from the same sheet material 402.
[0032] Embodiments of the present invention provide for easy
opening bags with only minor modifications to existing packaging
equipment and processes. Such easy open bags are more desirable for
consumers and relatively inexpensive to manufacture compared to
other types of easy open bags. Although the above discussion
mentions vertical form-fill-seal systems, embodiments of the
invention are not limited to such systems for making and filling
bags. Other bag filling and sealing systems, such as horizontal
fill machines and those that use pre-made bags, may be adapted to
implement embodiments of the present invention.
[0033] While the above is a complete description of the preferred
embodiment of the present invention, it is possible to use various
alternatives, modifications and equivalents. Therefore, the scope
of the present invention should be determined not with reference to
the above description but should, instead, be determined with
reference to the appended claims, along with their full scope of
equivalents. In the claims that follow, the indefinite article "A",
or "An" refers to a quantity of one or more of the item following
the article, except where expressly stated otherwise. The appended
claims are not to be interpreted as including means-plus-function
limitations, unless such a limitation is explicitly recited in a
given claim using the phrase "means for."
* * * * *