Note: Descriptions are shown in the official language in which they were submitted.
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LIQUID PLASTIC FILM POUCH WITH INNER STRAW
AND MACHINE AND METHOD OF MAKING
TECHNICAL FIELD
The present invention relates to a sealed
plastic film pouch containing a liquid and a free-
floating straw therein and wherein air is evacuated
from a space within the pouch to facilitate the
manipulation of the pouch by collapsing its side walls
to grasp the straw and puncture the pouch, and further
wherein the bag is formed from a multilayer film
having an inner sealant layer exhibiting a self-
sealing behavior about the straw in the punctured area
to provide a seal about the straw.
The invention also relates to the machine
and method for making a sealed liquid pouch having a
free-floating straw inside the pouch and more
particularly to the means and method for inserting the
straw within the pouch during the filling cycle of the
pouch.
BACKGROUND ART
It is known to form package liquid
containers with sealed plastic bags and wherein a
straw-like object or extractor is held inside the bag
and freely floating within the liquid contained
therein. Such a liquid pouch container is, for
example, described and illustrated in U.S. Patent
3,730,336 issued on May 1, 1973. Such package
containers, however, have disadvantages in that it
becomes difficult to manipulate the bag to grasp the
straw and puncture the bag due to the amount of liquid
and air held captive within the sealed bag. This
manipulation often causes the bag to burst It is
also important to have an added extra volume within
the bag in the event that it is desirable to freeze
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the package with its liquid content as the extra
volume will permit for expansion of the freezing
liquid content.
It is desirable with such bags to provide
straws with sufficient rigidity, such as polypropylene
to puncture the bag without having an end of the straw
cut on the bias and without having any means attached
to the straw to permit its grasping to facilitate its
movement within the bag as such means pose other
disadvantages in the automatic assembly of the pouch
with its liquid contents. It is also desirable with
such package liquid containers to provide a container
which is highly hygienic and which is formed of
plastic material which will not impart off-taste
(acidic taste) to a liquid contained therein and
particularly if the liquid is present for a long
period of time. It is further desirable with such
packaqes to extend the shelf life thereof so that such
packages with their liquid content can be maintained a
long period of time before being used. It is also
desirable to provide a plastic film pouch which can
provide a seal about the straw when the bag is
punctured and which can resist impact during handling
and shipping.
It is also known to manufacture plastic film
liquid pouches with a free-floating straw positioned
therein. Certain methods of manufacture utilize
forming the pouches by folding a film sheet
horizontally and placing a straw in the lower folded
section of the film strip well before the seals are
made to produce an open-ended pouch with a straw
therein ready to receive liquid. However, when
producing such pouches from vertical forming machines
where the film tube is formed in a vertical manner and
particularly in a continuously liquid dispensing
application, this task becomes much more difficult as
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the straw must be positioned within the bag being
formed as liquid is admitted in the bag due to the
continuous liquid dispensing process. This poses
several problems, one being the manner in which the
straws can be dispensed into the liquid pouch being
filled and also in synchronism with the pouch sealing
cycle. Another problem is to ensure that the straw
does not extend into the seal jaws after the open-
ended pouch formed in the plastic tube is disposed for
sealing the open top end to form the pouch. Another
problem is to adapt straw dispensing mechanism to such
bag forming and filling machines. It is also
desirable, during the manufacture of these sealed
liquid pouches, to evacuate some air from the space
which is formed in the bag and which is necessary to
provide for the expansion of the liquid, when it is
frozen.
SUMMAR~ OF INVENTION
It is therefore a feature of the present
invention to provide a plastic film pouch which
overcomes the above-mentioned disadvantages of the
prior art and which provides for the needs as above-
mentioned.
Another feature of the present invention is
to provide a sealed plastic film pouch having a liquid
and a free-floating straw therein and wherein a
predetermined quantity of air has been evacuated from
a space contained within the inner chamber of the
pouch.
Another feature of the present invention is
to provide a sealed plastic film pouch containing a
liquid and a free-floating straw therein and wherein
the plastic film is a multilayer film having an inner
sealant layer possessing a substantially self-sealing
behavior about the straw in a punctured area of the
,
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baq when in use whereby to provide a seal about the
straw.
Another feature of the present invention is
to provide a method of forming a plastic film pouch
with a liquid and straw disposed in the pouch and
which substantially overcome the above disadvantages
of the prior art and which meets the required needs.
Another feature of the present invention is
to provide a machine and a method for making a sealed
liquid pouch with a free-floating straw inside the
pouch, and which substantially overcomes the above-
mentioned disadvantages.
Another feature of the present invention is
to provide a machine for making sealed liquid pouches
with a free-floating straw inside the pouch and
wherein the straw is convected inside the pouch,
during the formation of the pouch, by a convection
tube and through which the straw freely falls by
gravity.
Another feature of the present invention is
to provide a machine for making a sealed liquid pouch
with a free-floating straw inside the pouch and
wherein the straw is inserted within the pouch being
formed during the displacement cycle of the plastic
film tube which forms the pouch.
Another feature of the present invention is
to provide a machine for making a sealed liquid pouch
with a free-floating straw inside the pouch and
wherein the formed plastic film tube is continuously
stretched laterally during the filling cycle and
sealing cycles and in conjunction with the sealing
jaws permits a certain ~uantity of air to be evacuated
from the free space in the pouch being formed.
Another feature of the present invention is
to provide a method of producing a sealed liquid pouch
having a free-floating straw located in the pouch and
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wherein a straw is simultaneously directed in the
liquid through a convection tube as the bag is being
filled and the tube being drawn to a sealing head.
Another feature of the present invention is
to further provide a method of producing a sealed
liquid pouch with a free-floating straw and wherein
air is evacuated from the space within the pouch
during the formation of the pouch.
According to the above features, from a
broad aspect, the present invention provides a plastic
film pouch for containing a liquid product. The film
pouch has opposed side walls sealed about a peripheral
edge thereof to define a sealed inner chamber. At
least a portion of at least one of the side walls is
formed of transparent film for visual access to the
inner chamber. A straw of predetermined rigidity is
located freely within the inner chamber. A liquid is
contained within the inner chamber and occupies from
about 60% to about 90% of the volume of the inner
chamber. The remaining volume of the inner chamber
has air evacuated therefrom in sufficient quantity to
permit the side walls to be collapsed against one
another to facilitate grasping the straw in the liquid
and manipulating it to puncture the plastic film pouch
whereby to extend a portion of the straw exteriorly of
the pouch to extract liquid from the pouch.
According to a further broad aspect of the
present invention, there is provided a method of
forming a plastic film pouch with a liquid and straw
disposed in the pouch. The method comprises the steps
of drawing a film web having opposed side walls
positioned in juxtapose to a filling and sealing
station. Edge seals are formed at the filling and
sealing station to form a pouch having an open-top-end
and defining an inner chamber. A straw, having a
predetermined rigidity, is inserted in the inner
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chamber through the open-top-end. A predetermined
volume of liquid is then inserted in the inner chamber
through the open-top-end to occupy from about 60% to
about 90% of the volume of the inner chamber and
thereby defining a vacant space thereabove The
opposed film side walls are then collapsed together in
a portion of the vacant space to expel air therefrom
through the open-top-end. A top edge of the two
juxtaposed side walls are then sealed together
adjacent the open-top-end whereby to form a pouch
having a liquid and a free-floating straw therein with
air evacuated in sufficient quantity to permit liquid
to be displaced within the inner chamber when opposed
side walls of the pouch are collapsed towards one
another to grasp the straw in the liquid and to
manipulate it to puncture the plastic film whereby to
extend a portion of the straw exteriorly of the pouch
to extract liquid from the pouch.
According to another broad aspect, the
present invention provides a machine for making a
sealed liquid pouch with a free-floating straw inside
the pouch. The machine comprises bag forming means
for making a bag from impervious plastic film
material. A filler mechanism is provided for placing
a liquid inside the bag. A straw convecting means is
provided for directing a straw in the pouch prior to
sealing the pouch.
According to a further broad aspect of the
present invention there is provided a method of
producing a sealed liquid pouch having a free-floating
straw located in the liquid within the pouch. The
method comprises the steps of folding and sealing a
plastic film sheet to form a film tube having an open-
top end. Liquid is inserted in the film tube and
simultaneously a straw is directed through a straw
convection tube for discharge into the liquid in the
, . . , . . .. ~
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plastic film tube. The plastic film tube is displaced
downwardly to a sealing jaw where a seal is formed at
an open top end of a filled film tube section to form
the sealed liquid pouch. The seal also forms a bottom
edge seal of another tube section being filled.
BRIEF DESCRIPTION OF DRAWINGS
A preferred embodiment of the present
invention will now be described with reference to the
accompanying drawings in which:
FIG. l is a perspective view showing a
plastic film pouch constructed in accordance with the
present invention and wherein a liquid and a straw is
contained within an inner chamber formed by the sealed
pouch;
FIG. 2A is a plan view of the plastic film
pouch of FIG. l and wherein the pouch is formed
entirely of transparent plastic materials;
FIG. 2B is a plan view showing the plastic
film pouch formed with an opaque rear wall and a
partly opaque and partly transparent front wall;
FIG. 3 is a perspective view showing how
the straw inside the plastic film pouch is manipulated
to puncture a corner portion of one of the side walls
whereby a portion of the straw can be exposed to
extract liquid from the pouch;
FIG. 4 is a perspective view showing the
pouch partly in section to show how the side walls of
the pouch are collapsed to grasp the straw;
FIG. 5 is an exploded view showing a
sealing membrane formed about the straw by the inner
sealant layer of the film which exhibits a self-
sealing behavior;
FIG. 6 is a section view showing the
composition of the multilayer resin film;
. . .
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FIG. 7 is a simplified side view
illustrating the method of forming the plastic film
pouch with the liquid and straw inserted therein and
the manner in which air is evacuated and in which the
bag is sealed;
FIG. 8 is a simplified side section view
further illustrating how the bag is formed and
particularly how air is extracted from the bag and how
the top and bottom seals are formed;
FIG. 9 is a simplified perspective view
showing a machine constructed in accordance with the
present invention for making filling and inserting a
straw in the liquid contained within a liquid pouch;
FIG. lO is a perspective view showing the
liquid pouch with the free-floating straw therein and
formed in accordance with the present invention;
FIG. ll is a simplified schematic view
showing the manner in which the film sheet is formed
into a vertical plastic tube to form the pouches as
shown in Figure 2;
FIG. 12 is a schematic perspective view
showing the straw storage and dispensing mechanism of
the present invention;
FIG. 13A is a simplified section view showing
the construction of the sealing jaws;
FIG. 13B is a view similar to Figure 5A but
showing a modification of the sealing jaws to provide
a means to expulse air from the bag being formed;
FIG. 14 is a top schematic view showing the
construction of the plastic tube engaging and
displacing mechanism; and
FIGs. 15A to 157C are schematic plan views
showing the dispensing of the straw within the plastic
bag being formed.
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DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings and more
particularly to Figure 1, there is shown generally at
the sealed plastic film pouch of the present
invention. A liquid product 11, as well as a free
floating straw 12, are contained within an inner
chamber 13 of the pouch 10. The plastic film pouch
has opposed side walls 14 and 15 which are sealed
about a peripheral edge 16 thereof. As hereinshown
the pouch 10 is formed of transparent film material
whereby to provide visual access to the free-floating
straw 12 and the liquid product. Of course, the film
material may be printed while still providing visual
access to the inner chamber thereof. As hereinshown
the front side wall 14 is provided with a printed
target area 17 to indicate to the user where it is
preferable to puncture the bag, although the straw can
be oriented to puncture other areas, but the corners
are preferred.
-20 The liquid product 11 contained within the
bag occupies from about 60% to about 90% of the volume
of the inner chamber 13. The remaining volume of the
inner chamber has a portion of air evacuated therefrom
in sufficient quantity to permit the liquid to be
displaced by collapsing the side walls against one
another to facilitate grasping of the straw.
Preferably, although not exclusively, the liquid
product contains approximately 84% of the volume of
the inner chamber. Also, these pouches are
preferably, although not exclusively, dimensioned to
contain liquid products in volumes from 3 ounces to 24
ounces.
As shown in Figures 2A and 2B, the plastic
film pouch 10 is of rectangular shape and is provided
with a bottom seal 18, opposed side seals 19 and 19'
and a top seal 20 about the opposed side walls 14 and
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-- 10 --
whereby to form a rectangular transparent film
pouch. It is pointed out that the film pouch need not
be entirely transparent and as shown in Figure 2B, the
rear side wall 15 is formed with a pigment to provide
a solid colored wall which is not transparent. On the
other hand, the front wall 14 may have opaque colors
printed on portions 14' thereof while maintaining a
large transverse transparent section 14' for visual
access of the straw 12 located within the pouch. Of
course, printed matter may also be applied across the
transparent section 14", provided one can still see
through the transparent section to locate the straw.
With reference now to Figures 3 to 5, there
will be described the manner in which the plastic film
pouch is used to puncture it with the inner straw and
to extract the liquid. As shown in Figure 4, because
air has been evacuated from the pouch, it is possible
to collapse the opposed side walls 14 and 15 by
pinching the pouch with the fingers 21 to grasp the
straw 12 with one hand. This permits the user to
manipulate the straw to position an end thereof
adjacent the target area 17 as shown in Figure 3.
With the fingers 22 of the other hand, the user grasps
a corner area 23 of the pouch and folds it downwardly
in the direction of arrow 24 against the straw free
end 12' with the target area 17 or an area close
thereto being pulled against the free end 12' whereby
the free end 12' will puncture the film and exit the
bag as shown in Figure 5.
In order to obtain a good seal between the
straw side wall 12" and the punctured hole 25, a
multilayer resin film material having an inner sealant
layer 26 is utilized. Such a multilayered film
material is illustrated in Figure 6 and it consists of
a laminated or extrusion-coated plastic film
comprising an inner sealant layer 26 which is selected
.. . . .
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from a linear low or very low density ethylene-octene
copolymer or a metallocene linear low density
polyethylene. Preferably, the sealant layer has a
density of 0.900 g/cm3 and above. The co-extruded
resin film also has at least a different outer polymer
27 or an additive which is preferably a multilayer
resin film blend of high pressure polyethylene or
other linear low density ethylene-octene copolymer.
It may also have a pigmented resin core 28 if it is
desirable to form the pouch with an opaque back wall
as previously described. The core could be a
barrier material, such as Nylon, PET, PVDC, PP EVOH,
for example. Such a multilayer resin film provides
for the fabrication of a pouch having excellent impact
and flexural properties to prevent leaking and
exhibits low heat seal initiation temperatures to
permit high speed sealing of the pouch. It is
preferable with these pouches that they be strong and
defect-free, that is to say that there are no pin
holes or folds which could lead to leaking pouches.
As the pouches are typically made on a
vertical formed fill seal packaging machine, the hot
tack properties of the film are important. The
multilayer film as shown in Figure 6 combines
different resins or additives in one or more layers in
order to achieve specific performance properties of
the pouch l0. As above-described, the important
aspect of this multilayer film is the inner sealant
layer 26. Metallocene low density ethylene-octene
copolymer is preferred as it does not impart off-
taste, that is to say it does not impart an acidic
taste to the liquid product when contained within the
bag over a long period of time. It also improves the
shelf life of the liquid product within the pouch.
Another polymer material such as EVOH or PET could be
used to provide barrier characteristics to the pouch.
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- 12 -
Furthermore, lower cost LLDPE butene or LDPE could be
used in the core to reduce costs.
With reference to Figure 5 it can therefore
be appreciated that because the inner sealant layer 26
exhibits a substantially self-sealing behavior about
the straw, it forms a sealing membrane 29 all about
the straw side wall 12" to prevent liquid from seeping
through the punctured hole 25. The liquid product
from the straw can be extracted by squeezing the bag
to expulse the liquid through the straw 12 or else the
liquid may be sipped out of the pouch through the free
end lZ' of the straw.
With reference now to Figures 7 and 8, there
will be described a method of forming the plastic film
pouch 10 of the present invention with a liquid 11 and
a straw 12 disposed in the pouch. This pouch 10 is
formed in a vertical form fill seal packaging machine,
not shown, and in which the two film sheets 14 and 15
are brought in juxtaposition but separated from one
another, as shown in Figure 7, and drawn on opposed
sides of a filler tube 30. The liquid product 11
flows from the dispensing end 31 of the filler tube
after the bottom seal 18 and side seals 19 and 19'
have been formed. Accordingly, the two plastic resin
film sheets 14 and 15 are drawn in juxtaposition to a
sealing and filling station 32 which is shown in
Figures 7 and 8. At this station the side seals 19
and 19' are formed as the bottom seal 18 was already
formed when the top end of the bag was sealed, as will
be described. The seals may be formed using impulse
or constant heat techniques or using any other
convenient sealing system, such as ultrasonic sealing.
By forming the side seals 19 and 19' a pouch
having an open top end 33 is formed. The straw 12 is
then injected into the open top end pouch by a straw
injector, as will be described later, through the
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space 34 as shown in Figure 8. The filler tube then
quickly dispenses a predetermined quantity of liquid
product within the open ended pouch and as previously
mentioned this product will fill from about 60~ to
about 90% of the volume of the inner chamber of the
pouch and preferably, but not exclusively, 84% of this
chamber. ~uring the filling, the pouch can also be
held by clamps, not shown. As soon as the liquid is
dispensed the filler tube 30 is retracted with the
liquid product reaching its maximum level as indicated
by reference numeral 35. Alternatively, the open-top-
end pouch could be advanced after the filling. As
soon as the filler tube is retracted, or its pouch
advanced, a pair of clamping arms 36 and 36' will
clamp the bag in the area depicted between the broken
lines 37, as shown in Figure 6, and spaced from the
open top end 33 of the bag, whereby to expel air from
the space on top of the liquid level surface 35. The
heat sealing head 38 and its back plate 39 then move
together to seal the top edge portion 40 of the open-
top-end bag to form the top seal 20 and simultaneously
the bottom seal 18 of the next bag to be formed is
also formed. As hereinshown the sealing head 38 is
provided with a series of perforating prongs 41 to
form a perforated line 42 between the seals 18 and 20
whereby the bags can be later separated from the strip
of bags being formed, as shown in Figure 8.
Referring now to Figure 9, there is shown a
vertical pouch forming machine 100 which comprises a
housing 111 having a dispensing conveyor 112
thereunder for dispensing liquid pouches 113 that are
formed by the machine. Because the liquid contained
within the pouches 113 is for human consumption, it is
important to maintain the machine in a sanitary
3~ environment and for this reason the vertical bag-
forming mechanism 114 is located inside the housing
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111 with air evacuated therefrom and access thereto is
provided by a door 115 having a transparent glass
panel 116 to provide visual access to the machine to
visualize the operation thereof and to detect any
malfunctions of its mechanisms. A control panel 117
provides adjustment and control for the various
mechanisms within the machine. A straw dispensing
magazine 118 is conveniently positioned on the top
wall 119 of the housing 111 and feeds, in a
synchronized manner, straws 120 from the magazine to
the top end of a straw dispensing tube 121 which
extends to or over the top end 119. A liquid
reservoir 122 or a feed pipe (not shown) feeds liquid
to a dispensing filler tube or spout tube 123.
As shown in Figure 10, the vertical forming
machine 100 forms the sealed liquid pouch 113 which
contains therein a substantially predetermined
quantity of liquid 124 and a straw 120 which is freely
floating therein. During the formation of the bag
from a sheet of film material, a transverse seal 125
is formed across one of the side panels 126 of the bag
113 and opposed side edge seals 127 and 128 are also
formed. The end edges 129 and 129' do not have seals
as they were formed by folding the plastic film sheet,
as will be described later. The end edge 129' may
constitute the top end of the formed bag. The side
panels 126 usually contain printed matter as is
described in our above-referenced co-pending patent
application.
Referring now to Figure 11 there is
schematically illustrated the construction of the
vertical bag-forming mechanism 114. It comprises a
plastic film tube forming head 130 which gathers
opposed side edge portions 131 and 131' of a film
sheet 132 which is pulled from a roll of film
material, not shown, and conveniently located within
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the housing 111 or externally of the housing and
guided by guide rolls 133. This forming head is known
in the art and its purpose is to fold the sheet and
overlap the side edge portions 131 and 131' by guiding
the side edge portions about the head 130 and under a
guide finger 134. This forms a hollow plastic tube
135. As hereinshown and with further reference to
Figure 14, it can be seen that this hollow plastic
film tube 135 is formed about the filler spout 123 as
well as the straw dispensing tube 121 which extends in
a side-by-side relationship with the filler tube 123.
The hollow plastic film tube 135 is advanced or pulled
in a downward direction, as indicated by arrow 136 by
a tube engaging drive mechanism 137. As shown in
Figure 14, this tube engaging drive mechanism
comprises a stationary support frame 138 in which is
supported opposed pairs of film engaging drive wheels
139 and 139'. Each pair of drive wheels 139, 139'
engage an outer side edge portion 140 and 140' of the
film tube 135. A drive motor, not shown herein,
actuates these wheels which are in frictional
engagement from opposed sides of the side edge
portions 140 and 140' of the film tube 135 whereby to
draw the film downwardly through the frame 138, a
predetermined distance as adjusted by the speed and
time of operation of the wheels. This tube engaging
drive 137 is only actuated between the opening and
closing cycles of the sealing mechanism 141 which will
be described later.
With further reference to Figure 11, while
the sealing mechanism 141 is actuated, there is
further actuated in synchronism therewith, a vertical
sealing mechanism 142 which seals the overlapped outer
edge portions 131 and 131' of the film sheet 132 along
a predetermined length. Accordingly, below the
vertical sealing head 142 there is formed an open-
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ended hollow plastic film tube. The vertical sealer
is well known in the art and will not be described in
detail herein. The filler tube or liquid dispensing
spout 123 has a liquid dispensing end 123' positioned
a predetermined distance above the sealing mechanism
141. A tube expanding means in the form of a pair of
outwardly biased pusher arms 143 and 143' are secured
to opposed sides of the filler spout adjacent the
liquid dispensing end 123' thereof and are spring-
biased outwardly by a spring mechanism not shownherein. These pusher arms 143 have smoothly curved
outer ends 144 and are of narrow thickness whereby to
engage the inner side ends 145 of the hollow plastic
film tube 135. Their purpose is to maintain the tube
taught and expanded in the area of the liquid
dispensing lower end of the filler spout and also in
the area of the transverse sealing mechanism 141 in
order to eliminate creasing along the seal.
As shown in Figure 13A, the transverse
sealing mechanism 141 is constituted by a pair of jaw
plates 146 and 147 with the jaw plate 147 constituting
a bumper and displaceable against the jaw plate 146
which is provided with a sealing diaphragm 148 behind
which a sealing wire 149 extends to form a seal across
the plastic tube 135. A pair of gripper elements 150
are also provided in the inner faces 147' and 146' of
the jaw plates 147 and 146, respectively, whereby to
engage a top end portion of the lower filled pouch
113' and a lower bottom end portion of the upper tube
section of the bag 113" being formed. As can be seen,
because these sealing heads project from the inner
faces of the jaw plates, they also expulse a small
quantity of air from the space 151 above the liquid
level 124' of the liquid 124 in the pouch 113', when
closed.
,
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- 17 -
Figure 13B shows a modification of the jaw
plates 146 and 147 and as hereinshown the inner face
146' of the jaw plate 146 is provided with a pair of
cavities, namely a lower cavity 152 and an upper
cavity 153. The lower cavity is deeper than the upper
cavity and these longitudinal cavities are shaped to
receive therein longitudinal protrusions or bars 154
and 155, respectively. The lower protrusion 154
extends from the inner face 147' of the jaw plate 147
a distance greater than the other protrusion 155. The
reason for this is as the jaw plates 146 and 147
close, the lower protrusion 147' will expulse air from
the space 151 as the opposed walls of the plastic film
tubes collapse in a split second before the other
protrusion 155 engages an upper part of the bag walls
prior to the sealing wire 149 contacting the collapsed
walls to form the seal. The upper protrusion 155 only
performs a bag grasping and collapsing operation. It
is important to grasp the lower end of the bag above
the sealing head as li~uid is continuously fed into
the hollow tube by the spout.
Referring now to Figure 12, there will be
described the construction and operation of the straw
storage and convecting means. As shown in Figure 11,
the straw convection tube 121 is a straight tube which
extends from an upper straw receiving end 121' to a
lower dispensing end 121". As better seen in Figure
12, the straw dispensing magazine 118 is a storage
container, loaded from the top, and herein formed of
transparent plastic material and has opposed parallel
side walls 160 and opposed end walls 161. The top
portion of the magazine is substantially rectangular
and dimensioned to contain a plurality of the straws
120 therein and all oriented in a substantially
parallel manner. The bottom end of the rectangular
upper portion has a funnel-shaped lower section 162
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whereby to direct straws into a dispensing throat
portion 163 at the bottom of the lower section 162.
Straws are aligned in this throat portion in parallel
side-by-side relationship and in a single row 164 as
hereinshown. A straw access aperture 165 is formed in
at least one of the space side wall extensions 166
which forms the dispensing throat portion 163. The
access aperture may also be provided in the opposed
side wall 166 and this permits access to the straws
should there be blockage or a malfunction in the
throat area.
Transfer means in the form of a piston
actuated pusher rod 167 is also provided. The pusher
rod 167 is secured to a piston cylinder 168 for axial
displacement of the pusher rod. The pusher rod is
reciprocated at between 40 to 60 lbs pressure. The
pusher rod has a straw engaging end 169 and the rod is
dimensioned so as to extend through a discharge
opening 170 formed at the bottom of the dispensing
throat portion 163 whereby to engage an end of the
lowermost one of the straws 120, and shoot it out of
the dispensing throat portion 165 at a high velocity
and into a guide tunnel 171. Because the pusher rod
167 extends through the discharge opening 170 the
straw which was lying on top of the discharged straw
within the discharge throat portion cannot fall into
the discharge opening 170 due to the fact that it is
occupied by the pusher rod which is of circular cross-
section much like the straw. The piston cylinder 168
is also operated in synchronism with the transverse
sealing mechanism 141.
As shown in Figure 12, the guide tunnel 171
is formed by opposed side walls 173 and a curved end
wall 172 to maintain the straw oriented for discharge
within the convection tube 121. The curved end wall
172 has a curved shape designed to cause the straw to
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orient itself from a horizontal position, at the
discharge opening 170, to a vertical position and in a
guided manner whereby the straw will enter the open
top end 121' of the straw convection tube 121 and fall
by gravity therein to be released within the bag. As
hereinshown, an oscillating plate 174 is disposed in
the funnel-shaped lower section 162 adjacent the top
end of the dispensing throat section 163 whereby to
cause the straws adjacent the dispensing throat
section, to adopt a substantially parallel
orientation.
Although not shown it is also contemplated
that a loading and discharging turret may be provided
between the discharge opening 170 of the straw
dispensing magazine 118 and the open top end 121' of
the straw convection tube 121. The turret would have
four straw receiving cavities disposed at 90 degrees
to one another and wherein the pusher rod 167 would
push the lowermost one of the straws 120 into one of
the straw receiving cavities. The turret would then
be indexed or displaced 90 degrees and at the same
time clamping the loaded straw in position. When the
straw receiving cavities reach a vertical position
after 270 degrees of rotation, the retention means or
straw clamping means would release whereby the straw
at the 270 degree position would be released in the
open top end 121' of the straw convection tube 121.
Referring now to Figures 15A to 15C and
particularly in Figure 15A, it can be seen that the
straw dispensing end 121" of the straw dispensing tube
121 is located a distance high enough from the
dispensing end 123' of the liquid dispensing tube 123,
and from the top edge 137' of the jaws 137,
sufficiently to permit the straw 120 to be ejected
from the dispensing tube 121 and into the liquid 124'
which is quickly rising within the plastic film tube
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portion 113" being filled. As previously described,
as the jaws 137 open, the plastic film tube 135 is
drawn downwardly at a predetermined speed which is
synchronized to the amount of liquid entering the
hollow plastic film tube or pouch 113" being formed.
One of these pouches can be formed approximately every
second. Accordingly, as the straw 120 is released
within the pouch being formed, the pulling action on
the hollow plastic film tube 135 causes the straw to
tilt freely towards the filler spout 123, as shown in
Figure 15B. This action is fairly quick as a bag is
being formed in less than one second with about 175
percent of the bag filled with the liquid. As the
straw tilts it clears the top portion of the bag 113'
to be formed sufficient to clear the jaw plates 146 of
the sealing mechanism 141.
Summarizing the method of operation, a
sealed liquid pouch with a free-floating straw, as
shown in Figure 10, is formed by the steps of
convecting a plastic sheet about a tube forming head
to form a film tube having an open-top end whereby
liquid can be inserted within the film tube through a
filler spout 123. Simultaneously, a straw is directed
through a straw convection tube 121 and is discharged
within the plastic film tube in the liquid being
dispensed in a pouch being formed. As the plastic
tube is pulled downwardly, and the straw tilts whereby
to clear sealing jaws which form a seal at an open top
end of a filled film tube section to form the sealed
liquid pouch and simultaneously to form a bottom edge
seal of another tube section being filled. The straw
is transferred from a straw storage magazine to a
loading location where it is re-oriented to enter an
upper straw receiving end of the straw convection
tube, which is a straight tube, and wherein the straw
falls by gravity therethrough and into the pouch being
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formed. The plastic tube is continuously maintained
in a stretch condition and by doing so the opposed
walls are close together and this evacuates air from
the space provided in the pouch. Leak-proof side edge
seals are formed to constitute the sealed pouch. The
sealing jaw plates are also provided with a gripping
means which may be adapted to further expulse air from
the space in the bag being formed as well as perform
their gripping function as above-described.
It is within the ambit of the present
invention to cover any obvious modifications of the
preferred embodiment described herein, provided such
modifications fall within the scope of the appended
claims.
