Note: Descriptions are shown in the official language in which they were submitted.
CA 02257708 2001-12-17
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METHOD AND APPARATUS FOR AUTOMATICAhhY hINING A CONTAINER
Field of the Invention
The present invention relates to methods and
equipment for lining containers. In particular, the present
invention provides a method and apparatus for automatically
opening and inserting a bag-type liner into a container.
Background of the Invention
A thin plastic liner or the like is often employed
in a shipping box or other container to increase the shelf-
life of foods or other perishable commodities or to prevent
leakage or spillage of product from a sealed shipping
container. Such plastic liners are often in bag form.
A common method of lining containers has been to
manually place the liner over the open end of the container
and then drawing the liner into the container using a vacuum
as shown in U.S. Patent No. 4,052,931 to Morse et al., or by
blowing the liner into the container as shown in U.S. Patent
No. 4,537,584 to Everman et al. Attempts have also been
made to automatically open the liner before placing the
liner over the open end of the container by using a vacuum
assembly as shown in U.S. Patent No. 4,522,012 to Nelson,
U.S. Patent No. 4,083,293 to Goldstein, and U.S. Patent No.
4,537,584 to Everman et a1. However, the use of such vacuum
assemblies in a totally automated lining process has been
problematic. Vacuum cup or vacuum bar assemblies in totally
automatic assemblies do not provide a positive grasp on each
side of the liner to enable the sides of the liner to be
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completely pulled apart. In addition, simply separating the
sides of the bag at the open end does not completely open
the bag since the sides of the bag tend to cling together
due to surface tension or
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CA 02257708 1998-12-31
other adhesion between the inner surfaces of the liner. If the liner is not
completely
opened before it is placed over the container, the liner can tear. Attempts to
break
such surface tension or adhesion while using vacuum cups or bars to separate
the sides
of the liner have been unsuccessful.
Another method is disclosed in U.S. Patent No. 5,059,084 to Krein. There,
two methods are discussed for installing a liner in a semi-tractor trailer. In
the first
method, an unopened liner is manually unrolled into the trailer with the open
end
facing the entrance of the trailer (no discussion is provided on how the liner
will be
unrolled or by what mechanism). A blower is secured to the open end and the
liner
inflated. When the liner is fully expanded, the open end can be sealed against
the
entrance using, for example, tension bars 28 and 30. In an alternative
embodiment
shown in Figure. 8 (see col. 5 line 8), the liner is unrolled and the open end
is sealed
against the entrance. A vacuum is drawn through a pair of vertical vacuum
members
24 inserted at the rear of the trailer near the door hinges. These members
evacuate the
air in the trailer, drawing the liner up against the trailer wall. Krein
suggests that
other kinds of vacuum arrangements can be used , such as horizontal members
extending from the door of the trailer back into the rear of the container.
However, '
Krein does not disclose whether such members would be permanently installed in
the
trailer, or simply inserted during the procedure. If the latter, Krein does
not suggest
where the members would be located or how they would be inserted and
withdrawn.
Yet another method is described in U.S. Patent No. 4,874,354 to Johnson et al.
There, a liner is positioned above a container with the liner opening facing
toward the
container. A jaw assembly grasps the liner and fits the unsealed end of the
liner
around the opening of the container; subseduently, the liner is inverted into
the
container using a vacuum created in the container using a plenum over which
the
container has been positioned. Once in the container, the liner expands in the
inverted
configuration to line the inside of the container. A drawback with this
invention is
that there must be sufficient room above the container to accommodate the jaw
assembly and an extended liner while the liner is being cuffed to the
container. This
is apparent from Figure 1 of the '354 patent wherein the liner is in an
extended
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CA 02257708 1998-12-31
configuration as it is being cuffed to the container. If the liner is not
extended, the
vacuum plenum will not be able to efficiently draw the bag into the container.
Furthermore, this invention will only work if the container is substantially
open at the
bottom for providing access of the plenum to the inside of the container.
Still further,
S with this device, the liner is inverted in the container. This can cause a
configuration
problem if a specific side of the liner must contact the inner surface of the
container.
For example, if one side of the liner is more or less water permeable.
What is therefore needed is a quick and reliable method and apparatus for
lining a container having one or two openings. Furthermore, the apparatus must
also
be compact so as to minimize its space requirements. Still further, the
apparatus must
allow for lining of a container without inverting the liner during the lining
process.
Summary
The present invention contemplates an apparatus for lining containers having
one or more walls and at least a first open end, comprising: means for feeding
a
flexible bag-type liner having walls, a sealed end and an unsealed end, a
clamping
means for grabbing the unsealed end of the liner and separating the walls at
the
unsealed end of the liner; and a vacuum means for drawing air out of the
container for
fully opening the liner in the container.
In one embodiment, the present invention contemplates a method for lining
containers with a flexible bag-type liner comprising the steps of: providing a
flexible
bag-type liner having a sealed end and an unsealed end, a container having at
least a
first open end, a plurality of clamps, and a means for drawing air from said
container;
suspending the liner in the container with the sealed end inside the container
and the
unsealed end outside the container; grabbing the unsealed end of the liner
with the
clamps; pulling the clamps apart to open the unsealed end of the liner; and
actuating
the means for drawing air from the container to open the liner in the
container, and
cuffing the unsealed end of the liner over the open end of the container.
In a preferred embodiment, the present invention contemplates a method for
lining containers with a flexible bag-type liner comprising the steps of:
providing a
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Continuous source of flexible liner having a generally tubular
shape, a leading sealed end; a cutting and sealing means; a
container having at least a first open end; a plurality of
clamps; and a means for drawing air from said container. In
one embodiment, the sealed end of the liner is dropped through
the first open end and into the container; engaging the liner
with the cutting and shaping means a predetermined distance
from the sealed end, thereby cutting off a section of the liner
to form an unsealed end, and creating a new sealed edge on the
continuous flexible liner; grabbing the unsealed end of the
liner with the plurality of clamps; pulling the clamps apart to
open the unsealed end of the bag; and actuating the means for
drawing air to draw air out of the container from between the
bag and the container, thereby fully opening the bag into the
container.
In another, more preferred embodiment, the sealed end
of the liner is dropped along the outside surface of the
container, the unsealed end is grabbed with a plurality of
clamps, and at least some of the clamps are moved away from the
other clamps to open the unsealed end of the bag and to draw at
least one side of the bag over the open end of the container
before actuating the means for drawing air to suck the liner
into the open end of the container, thereby fully opening the
bag into the container.
In either of these embodiments, the method further
comprises the step of cuffing the unsealed end of the liner
over the open end of the container.
In accordance with the present invention, there is
provided a method for lining containers with a flexible bag-
type liner comprising the steps of: (a) providing an unopened
flexible bag-type liner having a sealed end and an unsealed
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~466~-104
end, and at least one wall, a container having an interior
surface, at least a first open end, a means for drawing air
from said container, a means for suspending said liner above
said open end of said container, at least one pair of clamps,
said pair of clamps mounted so that a first clamp of the pair
is mounted on one side of liner and a second clamp of the pair
is mounted on an opposite side of said liner, with said first
clamp mounted for relative movement towards and away from said
second clamp of the pair and for interaction with said second
clamp for opening the unsealed end of said liner; (b)
suspending said sealed end of the unopened liner below said
first open end of said container, and said unsealed end of the
unopened liner above said sealed end of the liner and outside
of the container; (c) grabbing the unsealed end of the liner
with the clamps; (d) moving at least one of the clamps away to
open the unsealed end of the liner; and (e) actuating the means
for drawing air from the container to draw the wall of the
liner against the interior surface of the container thereby
substantially fully opening the liner in the container.
In accordance with the present invention, there is
further provided a method for lining containers with a flexible
bag-type liner, using an apparatus having a conveying means, a
container having a wall and at least one open end, said
container positioned on said conveying means, a vacuum means
mounted at a lining station along said conveyor, a continuous
source of flexible liner material of generally tubular shape
for forming liners having a wall, a leading sealed end, and an
open trailing end, said continuous source of flexible liner
material mounted above said lining station; a means for feeding
said flexible liner material along a predefined path; a cutting
and sealing means mounted above said lining station and along
said predefined path; at least one pair of clamps mounted above
said lining station and below said cutting and sealing means
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for opening said open trailing end of the formed liners, a
first clamp of said pair of clamps mounted on one side of said
predefined path and a second clamp of the pair is mounted
opposite said first clamp on an opposite side of said
predefined path; with at least said first clamp mounted for
relative movement towards and away from said second clamp; the
method comprising the steps of: (a) feeding the leading sealed
end of the unopened liner material along the predefined path
whereby said sealed end is suspended between the open end of
the container and the conveying means; (b) engaging the liner
material with the cutting and sealing means a predetermined
distance from the sealed end, to form a liner having an
unsealed trailing end; (c) moving the first clamp relatively
towards the second clamp until the wall of the liner at the
unsealed trailing end has been secured by the clamps; (d)
moving the first clamp relatively away from the second clamp to
draw the wall of the liner over the open end of the container
to open the trailing unsealed end of the liner; and (e)
actuating the vacuum means for drawing air out of the container
to draw the wall of the liner against the wall of the
container, thereby substantially fully opening the liner in the
container using vacuum alone.
In accordance with the present invention, there is
further provided an apparatus for lining containers having one
or more walls, an interior surface, a bottom and at least a
first open end, comprising: (a) a means for feeding a leading
sealed end of an unopened flexible bag-type liner having a
wall, a sealed end and an unsealed end, along a predefined
liner path, said predefined path extending from a first
position at said means for feeding generally downwardly to a
second position vertically below said open end of said
container where said sealed end is suspended prior to opening;
and wherein said predefined liner path includes a tray mounted
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74667-104
outside and adjacent to said container, said tray providing a
surface onto which the sealed end of the unopened liner can be
fed by the means for feeding; (b) a means for engaging and
separating the walls at the unsealed end of the liner after the
sealed leading end of the unopened liner has reached said
second position; and (c) a vacuum means for drawing the wall of
the liner against the interior surface of the container for
substantially fully opening the liner in the container.
In accordance with the present invention, there is
further provided an apparatus for lining containers having one
or more walls, an interior surface, a bottom and at least a
first open end, comprising: (a) a means for feeding a leading
sealed end of an unopened flexible bag-type liner having a
wall, a sealed end and an unsealed end, along a predefined
liner path, said predefined path extending from a first
position at said means for feeding generally downwardly to a
second position vertically below said open end of said
container where said sealed end is suspended prior to opening;
(b) a clamping means for grabbing the unsealed end of the liner
and separating the walls at the unsealed end of the liner after
the sealed leading end of the liner has reached said second
position; and (c) a vacuum means for drawing the wall of the
liner against the interior surface of the container for
substantially fully opening the liner in the container; said
predefined liner path including a tray mounted outside and
adjacent to said container, said tray providing a surface onto
which the sealed end of the liner can be fed by the means for
feeding.
In accordance with the present invention, there is
further provided an apparatus for lining containers having one
or more walls, an interior surface, a bottom and at least a
first open end with a liner having a sealed end, an unsealed
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~466~-104
end, and opposing liner walls, comprising: (a) a means for
feeding a leading sealed end of an unopened flexible bag-type
liner downwardly along a predefined liner path, said predefined
path extending from a first position at said means for feeding
generally downwardly to a second position vertically below said
open end of said container and said unsealed end of said liner
where said sealed end is suspended prior to opening; (b) a
means for engaging and separating the opposing liner walls at
the unsealed end of the liner after the sealed leading end of
the unopened liner has reached said second position, thereby at
least partially blocking the open end of the container with the
liner; and (c) a vacuum means for sucking the liner against the
interior surface of the container for substantially fully
opening the liner in the container, said vacuum means including
a switch for activating the vacuum when the clamping means has
separated opposing walls of the unopened liner at the unsealed
end and at least partially blocked the open end of the
container with the liner.
Likewise, in either of these embodiments, the means
for drawing air comprises a vacuum plenum over which the
container is positioned during lining. Alternatively, the
means for drawing air from the container comprises a plurality
of tubes communicating with a vacuum generator, said tubes
inserted into the container through the open end, before the
actuating step.
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Brief Description of the Figures
Figure 1 provides a perspective view of a
preferred embodiment of the present invention.
Figures 2A through 2G illustrate the sequence of
steps performed by the preferred embodiment of Figure 1 when
lining a container.
Figure 3 provides a perspective view of an
alternative preferred embodiment of the present invention.
Figures 4A through 4H illustrate the sequence of
steps performed by the alternative embodiment shown in
Figure 3 when lining a container.
Figures 5A through 5H illustrate a more preferred
sequence of steps performed by a more preferred embodiment.
Figure 6 provides a perspective view of the more
preferred embodiment shown in Figures 5A through 5H.
Detailed Description of the Preferred Embodiment
The following description serves to illustrate a
preferred embodiment and aspects of the present invention
and is not to be construed as limiting the scope thereof.
In considering the method and apparatus of the
present invention some definitions are helpful. For
example, "cuffing" refers to the process of forming a cuff
of the flexible liner along the outside open edge of the
container. A "means for drawing air" refers to any means
for drawing air from a container. This means does not
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necessarily create a vacuum but instead may include a means
for creating a near vacuum condition. "Grabbing" refers to
the clamps of the present invention engaging the sides of
the plastic liner. An illustration of a suitable clamp and
typical grabbing action can be seen in U.S. Patent No.
4,874,354 to Johnson et al.
"Inverting the liner/bag" refers to turning the
liner/bag inside-out. "Vacuum tubes" refer to tubes that
are coupled to a device for drawing air (i.e. a vacuum
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CA 02257708 1998-12-31
cleaner, a reversible blower, a fan blade). The tubes can have any cross
sectional
shape.
Figure 1 illustrates a perspective drawing of a preferred embodiment of the
present invention. Specifically, the device comprises a conveyor 2 for
supporting a
S container 6 such as a typical cardboard box. As with many cardboard boxes,
the
container 6 has a set of four flaps on the top and bottom for sealing the box.
The
container is placed on the conveyor 2 with at least two of the bottom flaps
open so
that the inside of the container is exposed to the vent 4. The vent 4 is
coupled to any
conventional means for drawing air from the inside of the container (i. e. for
creating a
vacuum or near vacuum condition). For example, a fan can be incorporated to
draw
air from the inside of the container 6.
Positioned above the container 6 are two rollers 14 for feeding a flexible
liner
16 (i. e. a plastic or latex liner), having a sealed end 21. Although
illustrated here as
employing two rollers, it should be apparent to one skilled in the art that
any means
for feeding a flexible liner can be used and this invention is not limited to
a particular
number of rollers or to rollers at all.
A clamp cylinder 12 and a knife 10 are preferably located directly beneath the
rollers 14 for cutting off a section of the liner and sealing the bottom edge
of the next
liner 24. The clamp cylinder 12 and knife 10 are designed in such a manner
that a
sealing means is located above a cutting means. This allows the clamp cylinder
12
and knife 10 combination remove a section of the liner wherein the liner
section has
an unsealed top 22, while the remaining liner is sealed at its bottom. By
sealing the
bottom of the remaining liner, the present invention ensures that upon the
next cycle,
the next liner section will have a sealed bottom edge 24. Any conventional and
well
known sealing means can be used such as those used to seal plastic food bags
(i. e. a
heated metal or composite strip). The cutting edge can be any edge sharp
enough to
cut through the liner. Alternatively, a roll of pre-sealed liners with
perforations for
separating one liner from the next can be used with the present invention.
Below the clamp cylinder 12 and knife 10 are clamps 8 for engaging the liner
section and spreading open the unsealed end 22 of the liner section. Although
the
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clamps 8 can be of any design for gripping the sides of a
liner and separating them, an example of a suitable design
is illustrated in U.S. Patent No. 4,874,354 to Johnson et
al. Furthermore, it is contemplated in the preferred
embodiment that four clamps 8 be incorporated roughly
located above the four corners of the container 6. This
does not preclude, however, the application of more or less
clamps or different positions of the clamps 8.
Figures 2a-g illustrate this preferred embodiment
in operation. In Figure 2a, the conveyer 2 positions a new
container 6 below clamps 8 while the two rollers 14 feed a
length of liner 16 (sealed end 21 first) into the container
6 through open end 7. When the appropriate length has been
fed, the clamp cylinder 12 and knife 10 engage the liner 16
thereby cutting a section of the liner 16 and sealing the
bottom edge 24 of the next liner in Figure 2B. While the
clamp cylinder 12 and knife 10 are still engaged, the clamps
8 grip the liner section below the clamp cylinder 12 and
knife 10 in Figure 2C. It should be noted that while shown
here in this order, the present invention should work
equally well if the clamps 8 grip the liner before the clamp
cylinder 12 and knife 10 engage. It should also be noted
that while a minimum of two clamps 8 are necessary for
proper operation, additional clamps may also be
incorporated.
In Figure 2D, the claims 8 open the liner section
by spreading apart the sides of the liner section. A vacuum
or near vacuum condition is then created in the container by
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. 74667-104
removing air from the container through open end 5 via the
vent 4. This draws the walls of the liner against the
inside of the container. The clamps 8 then cuff the liner
section over the top of the container by pulling the ends of
the liner section down around the outside of the open end 7
of the container 6 in Figure 2E. Once the liner section has
been cuffed, the clamps 8 open and clear the container 6 in
Figure 2F and the vacuum is stopped. Finally, the clamps 8
return to their original position as a new container is
moved into position as shown in Figure 2g. It should be
noted that while this embodiment describes the vacuum as
perfectly expanding the liner section in Figure 2d, such
expansion could also occur at step 2e or 2f and possibly at
step 2g.
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An alternate preferred embodiment is illustrated in Figures 3 and 4. Figure 3
is
a perspective diagram of the alternate preferred embodiment which is similar
to Figure
1 and having similar elements. Specifically, elements 8, 10, 12, 14, 16, 21,
22 and 24
are the same as the similarly numbered elements from Figures 1 and 2. Two
significant distinctions between this embodiment and the previous embodiment
are that
this embodiment incorporates vacuum tubes 18 and it can be utilized on a
container 20
having a closed bottom.
The vacuum tubes 18 are any tubes which are sufficiently able to draw air from
a container. For example, the tubes may be coupled to a fan or vacuum plenum
having sufficient suction power to expand the liner section in the container.
Furthermore, although the vacuum tubes 18 are illustrated as having a square
cross
section, they can have any cross sectional shape such as a circle, hexagon,
oval, etc.
The container 20 can be, although is not limited to, a cardboard box similar
to
container 6 illustrated in Figures 1 and 2, except that the bottom flaps are
closed
and/or sealed. Furthermore, the container 20 can be placed on a conveyor belt
for
automatic positioning of a new containers at the start of each cycle.
Figures 4a-h illustrate one cycle of the alternate preferred embodiment in
operation. Figure 4a illustrates the position of the different elements of
this
embodiment at the start of a cycle when a new container 6 is positioned. At
Figure
4B, rollers 14 feed a length of the liner 16 into the container while the
vacuum tubes
18 are lowered into the container 20 at its four corners. It should be noted
that while
described here as being inserted at the container's four corners, it is also
contemplated
that the vacuum tubes 18 be inserted at points other than the four corners or
at only
one, two or three corners. Furthermore, it is also contemplated that fewer
than four
vacuum tubes could be utilized.
In Figure 4C, a clamp cylinder 12 and knife 10 are preferably provided to
engage the liner 16 and cut a section of the liner 16 while simultaneously
sealing the
bottom end 24 of the next liner. However, as noted above, it would be possible
to use
pre-sealed liners perforated for easy separation. The clamps 8 also grab the
unsealed
end of the liner section during this step. In Figure 4D, the clamp cylinder 12
and
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CA 02257708 1998-12-31
knife 10 disengage and the clamps 8 and draw open the sides of the liner
section.
Meanwhile, the vacuum tubes 18 are activated to draw air from the space
between the
sides of the liner section and the sides of the container 20, thus forming a
vacuum.
This vacuum causes the walls of the liner section to be drawn against the
walls of the
container.
As shown in Figure 4E, the vacuum tubes 18 can then be deactivated and then
removed from the container 20, as the clamps cuff the liner section by pulling
the end
of the liner section down over the sides of the container 20 as shown in
Figure 4F.
The clamps 8 then release the liner section (Figure 4G) and return to their
start
position in Figure 4h. The container is then transported to a different
location while a
new container is positioned to be lined and the process is repeated.
A more preferred embodiment is shown in Figure 6. As discussed above, the
more preferred embodiment includes a conveyor 2 for supporting a container 6
such as
a typical cardboard box. As with many cardboard boxes, the container 6 has a
set of
four flaps on the top and bottom for sealing the box. It should be noted that
new
cardboard boxes, such as those typically used in packaging products, these
four flaps
are relatively rigid, upstanding elements which typically do not move or
interfere with
the lining and cuffing steps discussed herein. The container is placed on the
conveyor
2 with at least two of the bottom flaps open so that the inside of the
container is
exposed to the vent 4. The vent 4 is coupled to any conventional means for
drawing
air from the inside of the container (i. e. for creating a vacuum or near
vacuum
condition). For example, a vacuum plenum, or even a simple fan of sufficient
drawing
power, fan can be incorporated to draw air from the inside of the container 6.
Positioned to one side of the container 6 are two rollers 14 for feeding a
flexible liner 16 (i. e. a plastic or latex liner), having a sealed end 21.
Although
illustrated here as employing two rollers, it should be apparent to one
skilled in the art
that any means for feeding a flexible liner can be used and this invention is
not limited
to a particular number of rollers or to rollers at all.
A clamp cylinder 12 and a knife 10 are preferably located directly beneath the
rollers 14 for cutting off a section of the liner and sealing the bottom edge
of the next
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liner 24. The clamp cylinder 12 and knife 10 are designed
in such a manner that a sealing means is located above a
cutting means. This allows the clamp cylinder 12 and knife
combination remove a section of the liner wherein the
5 liner section has an unsealed top 22, while the remaining
liner is sealed at its bottom. By sealing the bottom of the
remaining liner, the present invention ensures that upon the
next cycle, the next liner section will have a sealed bottom
edge 24. Any conventional and well known sealing means can
10 be used such as those used to seal plastic food bags (i.e. a
heated metal or composite strip). The cutting edge can be
any edge sharp enough to cut through the liner.
Alternatively, a roll of pre-sealed liners with perforations
for separating one liner from the next can be used with the
present invention.
Below the clamp cylinder 12 and knife 10 are
clamps 8 for engaging the liner section and spreading open
the unsealed end 22 of the liner section. Although the
clamps 8 can be of any design for gripping the sides of a
liner and separating them, an example of a suitable design
is illustrated in U.S. Patent No. 4,874,354 to Johnson et
al. Furthermore, it is contemplated in the preferred
embodiment that four clamps 8 be incorporated which can be
positioned during the lining process roughly above the four
corners of the container 6. This does not preclude,
however, the application of more or less clamps or different
positions of the clamps 8.
CA 02257708 2001-12-17
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Below the clamps 8 is mounted a liner tray 30 and
a pivoting liner guide roller 32, the function of which will
be discussed below.
Figures 5A through 5H illustrate the operation of
this more preferred embodiment. In Figure 5A, the conveyer
2 has positioned a new container 6 over the vacuum plenum,
while the two rollers 14 feed a length of liner 16 (sealed
end 21 first) past guide roller 32 and onto the tray 30
positioned beneath the rollers 14 to one side of the vacuum
plenum. When the appropriate length has been fed, the clamp
cylinder 12 and knife 10 engage the liner 16 thereby cutting
a section of the liner 16 and sealing the bottom edge 24 of
the next liner in Figure 5B. while the clamp cylinder 12
and knife 10 are still engaged, the clamps 8 grip the liner
section below the clamp cylinder 12 and knife 10 in Figure
5C. It should be noted that while shown here in
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CA 02257708 1998-12-31
this order, the present invention should work equally well if the clamps 8
grip the liner
before the clamp cylinder 12 and knife 10 engage. It should also be noted that
while a
minimum of two clamps 8 are necessary for proper operation, additional clamps
may
also be incorporated.
In Figure SD, the clamps 8 open the liner section by relative movement away
from each other to separate the sides of the liner section, and to pull one
side of the
liner section, denoted as 26, over the open end of container 6, while the
clamp
cylinder and knife 10 separate to prepare for forming the next liner.
As shown in Figure SE, the vacuum plenum is then activated to create a
vacuum or near vacuum condition in the container, which rapidly draws sealed
end of
the liner into the container 6, and fully opens the bag in the container. All
that
remains outside of the container 6 is the open end of the bag which remains
secured
by the clamps 8.
As the clamps 8 move downward to cuff the open end of the liner over the
upstanding flaps of the container 6, as shown in Figure SF, the guide roller
32 pivots
away to avoid interfering with the cuffing process. The vacuum plenum remains
activated during cuffing. Once clamps 8 have reached the bottom of their
downward
stroke, the vacuum plenum is disengaged.
As shown in Fig. SG, the clamps open and return to their starting position,
while the guide roller 32 pivots back to its starting position. Then, the
conveyor
moves the lined container 6 away to be filled with product.
Fig. 5H shows a new container 6' positioned over the vacuum plenum, and the
components of the container liner in their starting position ready to begin
again the
process of lining container 6'.
In should be noted that in all embodiments, a liner section that has
previously
been cut to size, can be utilized. This would eliminate the need for the clamp
cylinder
12 and knife 10. Furthermore, it should be noted that the liner is not limited
to plastic
or latex, but may be composed of any material flexible enough to be expanded
by a
vacuum or near vacuum condition.
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From the above, it is clear that the present invention provides a quick and
reliable method and apparatus for lining a container having one or two
openings.
Advantageously, the apparatus allow for the lining of a container without
having to
invert the liner during the lining process. The invention has been described
in terms
of the preferred embodiment. One skilled in the art will recognize that it
would be
possible to construct the elements of the present invention from a variety of
materials
and to modify the placement of the components in a variety of ways. While the
preferred embodiments have been described in detail and shown in the
accompanying
drawings, it will be evident that various further modifications are possible
without
departing from the scope of the invention as set forth in the following
claims.
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