Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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~_PECIFICATION
Thls invention relates to plastic bags, and
it particularly relates to packs or pads comprising a
plurality of bag units stacked toyether and commonly
secured at a base portion in a manner to permit indi-
vidual bags to be removed from the pad while the pad
itself is supported in place.
There has been proposed the provision of a
pad of bags of the type disclosed herein with a hanger
means having a transverse portion that is arranged to
abut the selvage connecting means at the sides of the
base portion, whereby the hanger acts not only as a
hanger but also as a non-slippable internal supporting
means for the base portion. Such internal supporting
means was deemed necessary because the parts of the
bag-forming pockets that made up the base portion were
only extensions of the rear walls of these pockets.
These extensions formed single ply walls that had only
half the strength of the pockets themselves, where the
front and rear walls combined to form what was, in
effect, a double ply construction. This was an especially
significant problem when very thin plastic material was
used since, in such instance, even with the internal
support of the hanger, the base portion was still
relatively thln and flimsy and could not offer sufficient
opposing force when an individual bag was ripped away.
Such opposing force is required in order to cause auto-
matic opening of the mouth of the bags when it is pulled
away.
In addition, the process of making the above
r~r~
type pad of bags was relatively complicated and expen-
sive because the Eormation of the lips of the bags and
the selvage portions that formed the base portion
required very accurate machining to detailed specifi-
cations. This also limited the amount of production of
the pads.
Another problem heretofore was that the size
of the mouths and lips of the bags could not be easily
varied. The size of the mouth is often determined by
the article to be inserted in the bag, especially in
commercial use. A card or other thin object requires
only a narrow mouth whereas a larger article, such as
an apple or the like, requires a wider mouth. Heretofore,
for each size of article to be packed, the plastic film
or sheet material had to be especially processed for that
size article. This not only increased the complexity
and cost of production but also required a large inven-
tory to accomodate a variety of customers.
It was also difficult heretofore to use
plastic tubing for manufacturing the bags because of
the necessity of providing for the different lengths of
the front and rear walls. However, if it is possible
to use tubing, it makes the process easier and less
expensive.
It is an object of the present invention to
overcome the above and other problems by providing a
pad of bags with a base portion of relatively ~reat
strength even when very thin or flimsy plastic material
is used.
Another object of the present invention is to
provide a base portion which has a significant strength
relative to the individual bags whereby a sufficient
amount of opposing force is provided to cause opening
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of the bags as they are torn away from the pad.
Another ob~ect OI the present invention i5 to
obviate the necessity of using stiffening supports
in the base portion or of separate hanger means.
Another object of the present invention is to
provide a method of forming the mouth, lip and selvage
portions of the bag in a simple and inexpensive manner.
Another object of the present invention is to
provide a method of forming the mouths, lips and selvage
portions of the bags in such a manner that the size of
the mouth can be varied in accordance with the type of
article to be inserted into the bag.
Another object of the present invention is to
be capable of using plastic tubing instead of sheet
material that has to be pre-folded and pre-processed.
Other objects and many of the attendant
advantages of this invention will be readily appreciated
as the same becomes better understood by reference to
the following description when read in conjunction with
~0 the accompanying drawings whereino
Fig. 1 is a front perspective view of a
plastic bag embodying the present invention.
Fig. 2 is a sectional view taken on line 2-2
of Flg. 1.
Fig. 3 is a sectional view showing one
manner of forming the mouth, lip and selvage portion
of the bag.
Fig. 4 is a front perspective view of a pad
of bags of the type shown in Figs. 1, 2 and 3.
Fig. 5 is a fragmentary rear perspective view
of the pad of Flg. 4.
Fig~ 6 is a sectional view taken on line 6-6
of Fig. 4.
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, . :
Fig. I is a fragmentary rear perspective
view of another type of pad embodying the presenk
invention.
ig. 8 is a fragmentar~ front perspective
view of the pad of Fiy. 7.
Fig. 9 is a sectional view taken on line
9-9 of Fig. 8.
Fig. 10 is a fragmentary front perspective
view of yet another form of the invention.
Fig. 11 is a sectional view taken on line
11-11 of Fig. 10.
Referring in greater detail to the drawings
wherein similar reference characters refer to similar
parts, there is shown a plastic unit, generally
designated 10, comprising a front wall 12, a rear wall
14, a mouth 16 of the resultant bag-forming pocket 18,
with a lip being shown at 19, a sealed lower edge 20,
sealed side edges 22 and a selvage portion 24. The
selvage portion 24 is a double-walled extension of the
front and rear walls of the pocket 12 and is formed
by cutting a slot 26 in the front wall of a plastic
tube that is sealed at both ends. An example or the
cutting of such slot is illustrated in Fig. 3, where a
double-bladed cutting tool 30 is used. The slot forms
both the lip, defined by the lower edge 19 of the slot,
and the selvage portion, defined by the upper edge 32
- of the~slot. A score line 34 is the cut into the
selvage portion, as best shown in Fig. 1.
Figs. 4, 5 and 6 show the pockets or units 10
stacked to form a pad of bags) the pad being generally
designated 36. The pad 36 is formed generally in the
manner whereby the selvage portions are heat-..........
r ~ i ~ j r ~
sealed or welded together at their top edges, as at 40.
It is, of course, possi.ble to use other securing means
such as clamps, adhesive, rivets, etc., but hea-t-
sealing is preferred. The combined selvage portions
form the base portion 42.
The pad 36, is provided with a rear skirt or
flap 44 which is attached to the base portion 42 by
the same heat seals 38 and 40 that are used to attach
the selvage portions together.
The flap 44 may be made of the same or
different weight plastic than the pockets 10 and extends
up above the upper edge of the base portion to form a
ledge or hanger portion 46. Optionally, an adhesive
strip 48 may be provided along the upper rear edye
portion of the hanger portion 46. Any other desired
hanging means may be substituted, such as an aperture
to receive a hook or the like. The hanger may option-
ally also be reinforced, if so desired, by a strip of
rigid material or any other desired means.
The flap 44 and its hanger portion 46
constitute both an additional support for the base
portion, which is already of relatively good strength
because of the two-ply construction of the selvage
portions, and a built-in hanger means, thereby con-
siderably reducing the cost of materials and manufac-
turing which is inherent in the use of separate
reinforcing and hanging materials. In this respect,
since it is made of khe same or similar plastic
material as the remainder of the pad~ it can be
attached in the same heat-sealing operation used to
weld the selvage portions together. The hanger portion
does not even require a wall support since it can be
held in one hand while the other hand is used to pull
r~ rd
off a bag.
An alternative form of the invention is
shown in Figs. 7, g and 9. In this form, -the pad,
generally designated 100, is the same as in Figs. 4, 5
and 6 in that it comprises a stack of plastic units
102, each having a transverse slot 104 in its front
wall to form an open mouth and to divide the unit into
a bag-forming pocket 106 and a selvage portion 108.
The units are held toyether by welds 110 at the sides
and by welds 112 at the upper edges to form a base
portion 114.
A skirt or flap of the same or different
weight plastic material is provided at 116, this flap
being heat-sealed to the base portion by the same
welds that hold the selvage portions together. Elowever,
the flap 116 does not have an upstanding hanger
extension. Instead, it permits insertion of a rigid
support 118, made of metal, cardboard, wood or any
other desired rigid material. The upper end of this
support 118 is releasably but securely held between the
flap 116 and the base portion 114.
Another alternative form of the invention is
shown in Figs. 10 and 11 where the pad, generally
designated 200, is the same as that shown in Figs. 4,
5 and 6, including the pockets and the selvage portions
204 which are welded together at 206 and 208 to form
the base portion. The flap 210, which is secured to the
base portion by the same welds 206 and 208, has an up-
standing hanger portion 212 to which is secured a
rigid reinforcing strip 214 of any desired material such
as cardboard r paper, plastic, or the li]~e. An aperture
216, in the form of a grommet or the like, extends
through the hanger and its reinforcing strip ~or
, .
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receiving a hook or the li]ce. rrhis type of constructiOn
is especially suitable when very thin or flimsy plastic
material is used for the flap.
Although the construction of the units so far
described has been in the form of flexible plastic
tubing, it is possible, though less preferable, to use
flat sheets of plastic, pre-fold them to form the front
and rear walls and then seal the edges of the folded
sheets. These pre-processed units can then be processed
in the manner disclosed above to form the units and then
the pads.
Furthermore, although heat-sealed welds are
illustrated on the upper edge of the base portion, and
although these upper edge connections are preferably
used, it is possible to omit them and to utilize only
the welds at the side edges of the base portion since
these side edge connections have a significant effect
on the opening of the bags as they are torn away.
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