Note: Descriptions are shown in the official language in which they were submitted.
--1--
Description
Package
Technical Field
This invention relates generally to packaging devices,
5 and more specifically to flexible packages for containing
and dispensing liquids, solids, pastes and powders. The
invention is particularly applicable to sterilizable,
sterility maintaining packages for sterile products, such
as; for example, contact lens saline solution.
One of the major advances in modern packaging has
resulted from the mass production of flexible plastic
pouches used to contain a wide variety of materials.
Their low cost and ease of use have facilitated the
widespread use of many new products, including those in
15 the medical fieid. One of the problems associated with
such packages, however, particularly when they are used
as liquid containers, is how to easily open and dispense
the material contained therein. In addition, in the case
of packages for sterile products, a problem has been how
20 to open and dispense the sterile material contained
therein without contamination from the package.
Background Art
Previous attempts to overcome these difficulties are
illustrated in such patents as the following:
25 Pat. No. Title Inventor Issue Date
1,093,985 Detachable J. French Apr. 21, 1914
Secured label
1,607,626 Latex shipping E. Hopkinson Nov. 23, 1926
Bale
30 1,945,885 Device for H.S. Feb. 6, 1934
Opening Darlington
Containers
2,087,236 Individually E.R. Anders July 20, 1937
Wrapped bag
Package
--2--
Pat. No. Title InventorIssue Date
2,172,930 Dispensing D. BenselSept. 12, 1939
Container
2,293,952 Package J.H. StroopAug. 25, 1942
5 2,364,903 Bar for S.R. HowardDec. 12, 1944
Infusing
Material
2,676,702 Sanitary R. Whitefoot, Apr. 27, 1954
Package Jr.
10 2,760,630 Foil covered E.E. Lakso Aug. 28, 1956
Ampoule
3,157,312 Decoration D.M. Kitterman Nov. 17, 1964
Dispenser and
The method of
Filling, and
Dispensing
From the same
3,411,968 Method of I,.J. Vilutis Nov. 19, 1963
Incorporating et al
A tear string
In a
Thermoplastic
Web
3,426,959 Packaging J.H. Lemelson Feb. 11, 1969
Assembly
3,680,689 Enclosure with F. Grundschober Aug. 1, 1972
Progressively et al
Destructible
Seal
30 3,797,493 Single use E.C. SaudekMar. 19, 1974
Container,
Especially
For
Pharmaceutical
Material
While the packages illustrated in the foregoing patents
have met with some success none of them have provided a
practical low cost package for liquids with a dispensing
device integrally formed therein which allows the liquid
40 to be dispensed without puncturing or tearing the package.
This has posed problems in the case of sterile products
where the puncturing or tearing of the package leaves an
unsterile edge or surface over which the product must pass.
~..
-3-
Accordingly, it is an object of the present invention
to provide packages which may be easily opened and the
material contained therein easily dispensed. More
specific objects are:
- to provide such packages which can be sterilized
and the material contained therein dispensed
without contamination;
- to provide such pacXages in a form which
contains several materials which may be
retained separately until use is desired, and
- to provide such packages in a form which is easy
and inexpensive to manufacture.
Disclosure of Invention
The present 7 nvention comprises a container formed of
15 a sealable material with adjacent portions of the
container sealed together to close the container, thereby
effectively sealing a quantity of matter within the
container having an elongate stopper member disposed
transversely through the seal between the adjacent
20 portions of the package. The sealed portions are fused,
cemented or otherwise joined together so as to snugly
surround and frictionally engage the elongate stopper
member. However, in a preferred embodiment, the elongate
stopper member is not itself fused or cemented to the
25 package at the seal. Fusion is defined by Webster's
Seventh Collegiate Dictionary as, "the act or process of
liquifying or rendering plastic by heat". The elongate
stopper member has one end extending through the seal and
the other end extending outside the container in order
30 to allow the member to be grasped and withdrawn from
between the sealed portions without rupturing or tearing
the sealed portions. When the elongate stopper member is
withdrawn, an opening into the container through the
space formerly occupied by the elongate member is provided.
--4--
Matter within the container may be expelled through this
opening.
In a preferred embodiment the container is formed of
a plastic material having adjacent sheet portions heat
5 sealed together. Alternatively, the container may be
formed from plastic tube stock. The container may take
the form, among others, of a film plastic envelope or it
may comprise a blow-molded plastic bottle or vial. The
envelope may be a homopolymer, a copolymer, co-extruded
10 or laminated, such as polypropylene, polyvinylidene
chloride, polyamide or other well known packaging
materials. In addition, a foil laminate may be
integrally attached thereto in order to reduce water
vapor transmission. While in a preferred embodiment,
15 the entire container may be constructed of a flexible
material, in some instances the container may be
constructed of a rigid material which is compressed
about the elongate stopper member during the sealing
process. This compression may be accomplished through
20 the use of machinery or crimping devices such as a wire
crimp about the closure portion of the package.
In a preferred embodiment, the elongate stopper
member i5 composed of a substantially incompressible but
deformable member which constricts laterally and
25 stretches longitudinally when it is pulled away from the
container. This longitudinal stretching reduces the
cross section of the stopper allowing it to be withdrawn
from the container. The thickness and cross-sectional
area of the elongate stopper member is selected to
30 provide an opening of the desired size. In a preferred
embodiment the stopper is of a sufficient cross-
sectional area so that when removed, a fine stream of
matter may be expelled from within the container and
directed as desired. Alternatively, matter may be
35 dispensed drop by drop as required. In a preferred
embodiment the elongate member is comprised of a
flexible elastomeric material. Alternatively, the
,".1 ,
--5--
stopper member may be constructed of flexible plastic
material. In a preferred embodiment the stopper is
comprised of silicone rubber which can withstand
temperatures of 400F thereby resisting fusion to the
5 sealable material of the container as well as remaining
elastic and non-brittle at these temperatures. At the
same time silicone rubber easily deforms for removal
from the container. An example of such a silicone
rubber is Minnesota Rubber Co. number 71115 which is a
10 vulcanized cross-linked silicone which easily withstands
prolonged exposure to temperatures in excess of 400F.
An important element of the invention is the
propensity of the elongate member to deform both
longitudinally and laterally when force is applied during
15 sealing across a portion of the elongate member. When
the force of the sealing bars is applied across the seal
area of the container, the stopper deforms both toward
its ends, which are not under such force, and laterally.
The cross-sectional area of the elongate member stopper
20 in the seal area is relatively smaller when under such
force than the cross-sectional area of the elongate
stopper member when not under force. Since the stopper
is elastic, when force is removed from the seal area,
the stopper tends to return to its original shape,
25 expanding in the seal area and tightly engaging therein.
As a result, since the cross-sectional area of the
resultant opening through the seal is smaller than the
normal cross-sectional area of the elongate stopper
member, the elongate stopper member acts as a hermetic
30 seal of the opening between the inside and outside of
the package.
In order to effect elastic deformation of the stopper
member to seal the container, it must be constructed of
an elastic material, such as silicone rubber, which will
35 deform in the manner described. A second method for
effecting the elastic deformation of the stopper member
is through the use of a stopper having a selected cross-
--6--
sectional shape, such as a somewhat flattened ellipsehaving thin edges. Another way of describing this
shape would be to say it is almond shaped. This shape
tends to equalize longitudinal and lateral deformation
5 of the stopper when pressure is applied~ Another
preferred shape is formed by an arc subtended by a chord
which also equalizes deformation. An additional way in
which horizontal deformation may be limi~ed is to curve
the longitudinal edges of the stopper member with a
10 slight radius so that the edge will tend to be stopped
by, rather than penetrate the adjoining seal area when
being sealed into the container.
An elongate stopper member embodying one or more of
the above features may be withdrawn from the container
15 without rupturing either the seal or the container
material itself. This helps in packaging sterilized items
to insure a sterile dispensing path through the seal for
the material contained within the package when expulsion
from the container is desired. As mentioned previously,
20 the elongate member may be selected from a plurality of
thicknesses and shapes in order to provide the desired
size of dispensing orifice for the package.
In a preferred embodiment the container is both
sterilizable and sterility maintaining, (able to maintain
25 the product in a sterile condition), after being sealed,
in order to package medical products such as sterile
saline solution. This solution may be used to cleanse
contact lenses, for example, by withdrawing the elongate
member from the container and squeezing it, thereby
30 directing a fine stream of the saline solution onto a
contact lens. Alternatively, the solution may be
dispensed drop by drop.
An additional embodiment of the invention includes a
tab hermetically sealed to the container about the outside
35 end of the elongate member. That is, the tab is
hermetically sealed on the outside of the package around
the portion of the seal area adjoining the elongate
11~21~ -
--7--
member. This tab thus prevents the contamination of
that area until the package is opened. As a result,
when the tab and outside end of the elongate member are
removed, a sterile path for the material within the
5 container is provided.
A further embodiment of the invention includes the
use of plural compartments within the container. An
elongate member is disposed both between the compartments
and transversely through the end sea~ of the container.
lO Through the use of these plural compartments, a number
of different materials may be contained separately
within the container. For example, materials may be
stored separately and mixed immediately prior to use.
A further example of the use of such a container would
15 be the mixing of materials which are reactive or miscible
to form another material with short shelf life for point
of use application. A single dispensing orifice may be
used for both materials.
Brief Description of Drawings
FIG. 1 of the drawings is a front perspective view of
one embodiment of the invention.
FIG. 2 of the drawings is a front perspective view of
the embodiment shown in FIG. 1, showing the elongate
stopper member being withdrawn from the container.
FIG. 3 of the drawings is a perspective view of one
embodiment of the elongate stopper member used in the
improved dispensing package.
FIG. 4 of the drawings is a detailed partial section
view of the elongate stopper member in the seal area of
30 the package, and cross-sectional views of the elongate
member both within and outside of the seal area.
FIGS.4A and 4B are section views taken alon~ lines A-A
and B-B in Fig. 4.
FIG. 5 of the drawings is a perspective view of an
35 alternative embodiment of an elongate stopper member
used in the improved dispensing package.
'' ''i
--8--
FIG. 6 of the drawings shows a dispensing container
including a tab for hermetically sealing the container
dispensing area.
FIG. 7 of the drawings shows an alternative
5 embodiment of the invention including two compartments,
each of which may contain separate materials which may be
mixed before dispensing.
FIG. 8 of the drawings shows an alternative
embodiment of the invention including a blow-molded
10 plastic bottle as the container.
FIG. 9 of the drawings is a detailed partial
sectional view of one embodiment of the invention in which
the closure portion of the container is compressed about
an elongate stopper member.
FIG. 10 of the drawings is a detailed partial side
view of one embodiment of the invention in which a metal
band is crimped about the closure portion of the package,
with the elongate stopper member thereby frictionally
engaged within.
FIG. ll of the drawings is a detailed view, partly in
section, of one embodiment of the invention wherein the
elongate stopper member has a series of nodules attached
along its length which allow opening and resealing of the
container by progressively withdrawing the stopper member.
FIG. 12 is a side view of a schematic drawing of a
sealing bar means prior to exerting pressure against the
elongate stopper member during sealing.
FIG. 13 is a side view of a schematic drawing of
sealing bar means of FIG. 12 in which the sealing bar
30 has been compressed against the elongate stopper member.
FIG. 14 of the drawings shows generally the four
stages required to manufacture the container shown in
FIG. l.
FIG. 15 of the drawings shows an alternative
35 embodiment of an elongate member sealed into the container.
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g
FIG. 16 of the drawings shows another embodiment of
the manufacturing method used to produce the container
shown in FIG. 1.
Best Mode for Carrying Out the Invention
While this invention is susceptible of embodiment in
many different forms, there are shown in the drawings
and will herein be described in detail several specific
embodiments with the understanding that the present
disclosure is to be considered as an exemplification of
10 the principles of the invention and are not intended to
limit the invention to the embodiments illustrated.
A container 10 compris~s adjacent portions 12 and 14
of sealable material joined together to close container
10 with matter 16 effectively sealed therein. Portions
15 12 and 14 in a preferred embodiment, may be constructed
from flexible plastic sheet (greater than 10 millimeters
in thickness), film (less than 10 millimeters in
thickness) or tube stock. An elongate stopper member 18
is disposed between adjacent portions 12 and 14 and
20 extends generally transversely through seal 20 between
adjacent portions 12 and 14. Ad~acent portions 12 and 14
are joined at seals 20 and 20a by fusion, by means of
heat sealing, by cement, or adhesives, as desired, so as
to tightly grip elongate stopper member 18 at seal 20.
25 Elongate member 18 has one end 22 extending through seal
20 and the other end 24 extending outside the container.
This provides a portion 26 of elongate stopper member 18
which may be grasped and withdrawn from between sealed
portions 12 and 14, leaving an opening 28 into the
30 container through the space formerly occupied by elongate
member 18 through which matter 16 within the container
may be expelled from the container.
The container 10, shown in FIG. 1, is a flexible
envelope preferably formed of heat sealable plastic
35 material. The envelope may be of a single polymer such
as polyethylene, polypropylene, polyamide or
--10--
polyvinylidene chloride or of several copolymers. In
addition, a foil laminate may be integrally attached to
the film in order to inhibit water vapor transmission.
A further advantage of foil laminates is that after
5 opening, the pouch may be folded or crimped several
times at the top and thereby be reclosed. The folds
may also be held in place by a plastic or metal clip,
thereby holding the laminate in a closed position.
As shown in FIG. 2 of the drawings, the elongate
10 member 18 may be pulled away from container 10, thereby
deforming elongate member 18 by stretching it away from
the container. Upon stretching of elongate stopper
member 18 it tends to contract; to become smaller in
cross section than the inside cross section of opening 28
15 itself. As a result, elongate member 18 may be easily
removed from opening 28, leaving opening 28 open for
expulsion of the matter 16 within container 10. By
selection of an elongate stopper member of sufficiently
small cross section, opening 28, (created about elongate
20 member 18), is small enough to allow a fine stream of
matter 16 from within container 10 to be directed from
the container. Alternatively, matter 16 may be dispensed
drop by drop. In one embodiment, the material 16
contained within container 10 may be a sterile saline
25 solution used, for example, to cleanse contact lenses.
The saline solution is dispensed onto the contact lens
or into a lens carrying case. In this and other
embodiments, container 10 is formed of a sterilizable
material which maintains the sterility of matter 16
30 within the container once it is initially sterilized.
It should be noted that when elongate member 18 is
withdrawn from container 10, sealing area 20 is not
ruptured or torn. Consequently, opening 28 is intact
and material 16 may be dispensed through opening 28
35 without contacting a torn or contaminated area. (A
contaminated surface is one which has been exposed to a
non-sterile environment.)
In alternative embodiments the container may be used
to dispense foodstuffs, such as ketchup, liquid or
powdered air freshener, or even an anti-personnel
repellant such as a lacrimator like ethanol 2 chloro-l-
~M
5 phenyl. tMace ) Similarly, powders such as talc,insect powder or deodorant could be dispensed, or pastes
such as toothpastes.
In its preferred embodiment, elongate stopper member
18 is comprised of a flexible elastomeric material, and
10 is greater in length than in thickness. Alternatively,
elongate member 18 may be comprised of a flexible plastic
material. The member may be of a single or several
filaments. Silicone rubber such as Minnesota Rubber Co.
No. 71115 compound is a particularly suitable material
15 for elongate stopper member as it effectively resists
melting to container 10 when container 10 is sealed and
remains elastic and non-brittle at elevated temperatures.
It is also sufficiently stretchable to allow easy
withdrawal of member 18 from container 10. As shown in
20 FIG. 3, in a preferred embodiment elongate member 18
deforms both longitudinally and laterally when force is
applied during sealing across sealing area 20. As a
result, ends 22 and 24 are displaced away from seal 20
during sealing and the thickness of elongate member 18
25 within sealing area 20 is reduced. As shown in FIG. 4,
when force is removed from sealing area 20, ends 22 and
24 tend to contract to their original configuration
within sealing area 20 but cannot, due to the reduced
size in cross section of opening 28. The elongate
30 member 18 is thus tightly engaged in the opening.
Conse~uently, elongate member 18 acts as a hermetic
(airtight) seal of opening 28. It should be noted that
while elongate member 18 is shown in the configuration
of a cord, it may also take the form of 2 plug, a
35 stopper, a cap, an insert, or a body which is sealed to
the container having a removable core.
-12-
The cross-sectional shape of the elongate member 18
also helps to control the longitudinal and lateral
deformation of elongate member 18 when sealed within
sealing area 20 of container 10. As shown schematically
5 in FIG. 3, when elongate member 18 is sealed within
sealing area 20, force is applied from above and below
elongate member 18. As a result of this force, elongate
member 18 deforms in opposite directions longitudinally
and laterally, thereby thinning that portion 19 of
10 elongate stopper member 18 within the seal area 20.
Another way of describing this would be to say that
sealing force applied to portion 19 of elongate stopper
member from above and below causes ends 22 and 24 of
elongate member 18 to move away from the seal area 20.
15 As shown in FIG. 4, as a result of this moving away or
deformation, when sealing sealing area 20, the space
occupied by elongate member 18 in seal area 20 is thinner
in cross section than the remainder of member 18. When
elongate member 18 trys to return to its original shape
20 within opening 28, it cannot, because it is restricted
from doing so by the smaller size of opening 28. As a
result, elongate member 18 tightly fills and seals
opening 28 into container 10.
In order to control both lateral and longitudinal
25 deformation of elongate member when sealing force is
applied, elongate member 18 is formed in a number of
cross-sectional configurations. For example, as shown in
FIG. 3, elongate member 18 may be shaped in cross section
as a flat ellipse with pointed ends similar to the cross
30 section of an almond. Due to this somewhat flattened
configuration, deformation laterally and longitudinally
is equal, because, we believe, it is somewhat easier for
member 18 to deform towards its ends 22 and 24. Another
factor which facilitates such deformation is the fact that
35 elongate member 18 is composed of a material which is not
compressible. That is, it can change shape but not volume.
-13-
Therefore, it deforms longitudinally and laterally when
sealing force is applied. Another example of a shape
which may be utilized to limit lateral deformation is
shown in FIG. 5 of the drawings wherein the cross-
S sectional configuration of elongate member 18 is the areaencompassed by an extremely long arc subtended by a chord
to provide one side which is flat and the other side
slightly rounded. Again, this somewhat flattened
configuration does not allow much lateral deformation.
10 In both the embodiments shown in FIG. 3 and FIG. 5 of
the drawings the edges l9A and l9B of elongate member 18
are somewhat sharp rather than rounded. Consequently, as
a result of the proper selection of materials and cross-
sectional shape, when elongate member 18 is sealed within
15 sealing area 20 of container 10 and sealing pressure is
released, elongate member 18 snugly fills opening 28 in
the container 10. The thickness and shape of elongate
member 18 are designed to provide the desired size of
dispensing orifice 32 from container 10.
As shown in FIG. 6 of the drawings, in an alternative
embodiment, container 10 may include a tab 34 sealed to
the area 36 adjacent to outer end 26 of elongate member
18. Member 18 is thereby hermetically sealed within
container 10 and tab 34, but tab 34 itself is not sealed
25 to elongate stopper member 18. In order to dispense
material 16 from container 10, tab 34 is removed from
the package or opened, and elongate member 18 withdrawn.
If container 10 has been sterilized, area 36 ad~acent to
outer end 26 of elongate member 18 will remain
30 uncontaminated, until the opening has been closed within
tab 34. Material 16 contained within container 10 may
then be dispensed through opening 28 and out of orifice
32 without contacting a contaminated portion of the
package. This feature is particularly desirable for
35 dispensing sterilized products.
r~ `
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21~1
-14-
As shown in FIG. 7 of the drawings, in an
alternative embodiment, container 50 includes
compartments 52 and 54 for containing and dispensing
materials 56 and 58. In the embodiment illustrated,
5 material 56 may, for example, be a liquid and material
58 may be a solid which may be dissolved by the liquid
56. Elongate stopper member 60 extends between
compartments 52 and 54 through seal area 62 which
separates compartments 52 and 54. When it is desired to
10 use the material 56 and 58, elongate stopper member 60 is
partially withdrawn from compartment 52 and into
compartment 54. Stopper 60 is also moved partially
through seal area 20. The liquid material 56 within
compartment 52 may then be dispensed into compartment 54
15 by squeezing compartment 52 whereby the liquid 56 contacts
solid material 58 and dissolves it. The resulting
solution may then be dispensed by completely withdrawing
elongate stopper member 60 from container 50 thereby
leaving opening 64 free for expulsion of the solution.
As shown in FIG. 8 of the drawings, in an alternative
embodiment, container 70 may be a container of any desired
type or configuration such as a blow-molded plastic bottle
sealed at end 72. Sealed area 72 may be sealed by heat
sealing, microwave, adhesive, crimping, or other commonly
25 known means of enclosure. Elongate member 74 extends
through the seal 72 from the inside 76 to the outside 78
of container 70 and may be withdrawn in order to expel
material 80 contained within container 70. In order to
dispense material 80 within container 70 after member 74
30 is removed, the container is squeezed thereby collapsing
bellows 82 and reducing the volume within container 70,
and forcing material 80 from within the container 70
through opening 84.
As shown in FIGS. 9 and lO of the drawings, while in
35 a preferred embodiment, the entire container lO may be
constructed of a flexible material, in some instances the
- -15-
container 10 may be constructed of a rigid material
which may be compressed about the elongate stopper
m0mber 18 during the sealing process. ~his compression
may be accomplished through the use of machinery or
5 crimping devices such as a metal band 86 or wire crimp
about the closure 88. In these embodiments, stopper
member 18 may comprise a substantially rigid material
such as a length of metal wire.
As shown in FIG. 11 of the drawings, elongate stopper
10 member 18 may be formed with a series of nodules 92,
ripples or bumps along its length either integrally
formed or attached thereon. When elongate stopper member
18 is partially withdrawn from container 10, which may
be like any disclosed herein, and thin section 94 is
15 within opening 28, material may be dispensed through the
opening. The opening 28 may be resealed by pulling
elongate stopper member 18 further out of the container
10, causing nodule 92 of member 18 to once again seal
opening 28. Alternatively, a plug could be inserted into
20 opening 28 to reseal the container 10.
Shown in FIGS. 12 and 13 of the drawings are one
method of engaging elongate member 18 within container
10. As shown schematically, the elongate stopper member
18 within container 10 is disposed between heat platen 100
25 and sealing bar means 102. In a preferred embodiment,
sealing bar means 102 is comprised of a rubber compound
such as silicone rubber, 30-40 Durometer in hardness, of
the open cell type supplied by such manufacturers as
Dow Corning and Connecticut Rubber which can be selected
30 to deform under pressure as desired. While elongate
member 18 tends to deform laterally under pressure, the
deformation of sealing bar 102 about elongate member 18
tends to constrict such lateral deformation. As a result,
during sealing the force exerted by the sealing bar means
35 102 tends to eliminate cavities 104 and 106. After
sealing when the force is removed, elongate member 18
Z~
-16-
attempts to return to its original configuration but
cannot, due to the tight fit between the member 18 and
the container 10. A hermetic seal is thereby provided.
As shown in FIG. 14 of the drawings, the invention
5 includes stages in a method of manufacturing the
container 10 previously described. In part (a) of the
Figure, adjacent portions 12 and 14 of container 10 are
sealed together using conventional sealing techniques
such as heat sealing, shortwave, adhesive, impulse
10 sealing or other commonly known methods of enclosure.
If container 10 is comprised of sheet material, then the
container may be sealed on sides lOA, lOB and lOC or
folded and sealed on sides lOB and lOC. If it is
comprised of plastic tube stock then it is sealed only
15 along the bottom lOA. In part (b) of the chart material
16 is dispersed into container 10 again using
conventional filling techniques such as tube type filler
200. In part (c) of the Figure, elongate member 18 is
inserted into and held stationary proximate to the top lOD
20 of container 10. Elongate member 18 both extends into
and from container 10. Finally, in part (d) container 10
is hermetically sealed across top lOD of the container,
in seal area 20, with elongate member 18 tightly engaged
therein. As a result, container 10 may be now used to
25 store material 16 until ready for use.
As shown in FIG. 15 of the drawings in an alternative
embodiment, elongate member 18 may be sealed within
sealing area 20 of container 10 with a removable core
section 18A running longitudinally through it. In order
30 to dispense material 16 from container 10, removable core
section 18A is removed leaving an opening 18B for the
passage of said material 16.
As shown in FIG. 16 of the drawings, the invention
includes a novel method of manufacturing the container 10
35 previously described. In part (a) of FIG. 16, elongate
deformable member 18 has been inserted into container 10
-17-
by gripping arms 250 and 252 or by other appropriate
means. Once inserted into container 10, a portion 254
of said elongate deformable member 18 below seal area 20
is gripped between adjacent portions 12 and 14 of
5 container 10 by gripping arms 256 and 258. Alternatively,
elongate deformable member 18 may be gripped from within
container 10. Gripping arms 250 and 252 are then moved
away from gripping arms 256 and 258, thereby stretching
elongate deformable member 18.
As shown in part (b), stretching of elongate
deformable member 18 reduces the cross-sectional area of
portion 260 of elongate deformable member 18 lying in
seal area 20. When seal area 20 is then sealed, as shown
in part (c), portion 260 remains reduced in cross section.
15 This provides greater compressive force by elongate
deformable member 18 against opening 28, since elongate
deformable member 18 is elastic and seeks to return to
its original cross-sectional configuration. A tighter
seal may thereby be provided. As a result, opening 28
20 may be made smaller by stretching elongate deformable
member 18 than if it were sealed in said area 20 without
stretching. Alternatively, the stretching of elongate
member 18 with its correspondingly greater compressive
force allows the use of larger elongate members, and
25 therefore larger openings, when desired.
The foregoing description and drawings merely
explain and illustrate the invention and the invention
is not limited thereto, except insofar as the appended
claims are so limited as those skilled in the art who
30 have the disclosure before them will be able to make
modifications and variations therein without departing
from the scope of the invention.
, ~
