U.S. patent number 3,669,346 [Application Number 04/838,926] was granted by the patent office on 1972-06-13 for quick opening container.
This patent grant is currently assigned to The Pillsbury Company. Invention is credited to James R. Leezer, Francis R. Reid, Jack J. Rejsa, Charles H. Turpin.
United States Patent |
3,669,346 |
Leezer , et al. |
June 13, 1972 |
QUICK OPENING CONTAINER
Abstract
A cylindrical dough can including a body wall formed from two
rectangular sheets of approximately equal size bonded together with
two pairs of corresponding edges out of alignment so as to form two
extensions. The body wall is made into a tube with the extensions
bonded together in overlapping relationship along a permanent
longitudinally extending seal. Within the body wall is a thin fluid
impervious sealing liner, e.g., a foil having a mechanically weak
but fluid tight inner seal isolated from the longitudinal seal. A
provision such as a tear string is used for severing the outer
sheet along a line spaced circumferentially from the overlap area.
When pulled, the string penetrates the complete thickness of the
outer sheet thereby providing a flap which serves as a pull tab.
When the pull tab is lifted, tension is transmitted from the outer
extension to the inner extension through the permanent seal thereby
separating adjacent cut edges of the inner sheet from one another.
The inner seal is then opened.
Inventors: |
Leezer; James R.
(Jeffersonville, IN), Reid; Francis R. (Minneapolis, MN),
Turpin; Charles H. (Louisville, KY), Rejsa; Jack J.
(Minneapolis, MN) |
Assignee: |
The Pillsbury Company
(Minneapolis, MN)
|
Family
ID: |
25278410 |
Appl.
No.: |
04/838,926 |
Filed: |
July 3, 1969 |
Current U.S.
Class: |
229/201; 229/4.5;
206/830 |
Current CPC
Class: |
B65D
3/265 (20130101); Y10S 206/83 (20130101) |
Current International
Class: |
B65D
3/26 (20060101); B65D 3/00 (20060101); B65d
003/26 () |
Field of
Search: |
;229/51,4.5 ;99/172 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Norton; Donald F.
Claims
We claim:
1. A pressure-retaining tubular container comprising a
substantially cylindrical core formed from at least a pair of
sheets of material each having four edges, said sheets being bonded
together with two pairs of their corresponding edges out of
alignment to provide a pair of longitudinally oriented extensions,
said core being formed into a tube with the extensions positioned
in overlapping relationship thereby defining outer and inner butt
joints extending between the ends of the cylindrical core, a
permanent bond between the overlapping extensions, an end closure
member affixed to at least one end of the tube, a means for tearing
the outer sheet of the core along a line extending longitudinally
of the container outside of the overlapped area closer to the inner
butt joint than the outer butt joint, the outermost extension
defining a pull tab from the material of the outer sheet between
the tear means and the overlap area which when lifted and pulled
toward the overlap area transmits forces from the pull tab through
the permanent bond to the inner sheet so as to separate the
adjacent edges of the inner butt joint from one another and thereby
open the container, a piece of sheet material extends
circumferentially from the inner butt joint over the outer surface
of the inner sheet, at least the free marginal edge thereof is
removably adhered to the overlying surface of the outer sheet and
the opposite edge thereof is connected to the adjacent
longitudinally extending edge of the underlying sheet, whereby a
free swinging panel is defined to provide a space to receive the
expanding dough as the package is opened.
2. The container of claim 1 wherein, said piece of sheet material
is a liner adhered to substantially the entire inner surface of the
core, one edge of the liner being folded outwardly over a
longitudinally extending edge of the inner sheet and bonded to the
outer surface thereof to form a fixed hem and the opposite edge of
the liner is folded outwardly over the outer surface of the liner
and its free marginal edge portion is bonded to the overlying
surface of the outer sheet.
3. A container according to claim 2 wherein the bond between said
free edge of the liner and the outer sheet is formed with a heat
sealing adhesive.
4. The container according to claim 2 wherein the bond between the
fixed hem and an overlying portion of said core is formed from a
heat sealing adhesive.
5. The container according to claim 1 wherein a lead-in sheet
formed from a fluid impervious sheet material is bonded to the
inner surface of the outer sheet in the area between the overlap of
the extensions and the tear means and a liner formed from sheet
material is bonded to the inner surface of the inner sheet and is
folded outwardly over the adjacent edges of the inner butt joint
and is bonded to the overlying portion of the lead-in sheet to
prevent the leakage of fluids from the container.
6. The container according to claim 1 wherein the overlap area
extends parallel to the longitudinal axis of the cylinder.
7. The container according to claim 1 wherein the tear means
comprises a tear tape bonded to the inside surface of the outer
sheet.
8. The container according to claim 1 wherein a pair of circular
end closure members are removably crimped to the ends of the tube
whereby the pulling of the pull tab outwardly will cause the edges
that are crimped into the end closure members to be withdrawn from
the closure members as the container is opened to permit the
container to be opened.
9. A can comprising a tubular body wall, at least one end closure
member affixed to one end of the body wall to provide a bottom for
the container, said body wall being formed from at least a pair of
sheets each having four edges and being bonded together over at
least a portion of their contacting surfaces and having overlapping
extensions defining nonaligned outer and inner longitudinally
extending butt joints, a tear means for serving at least the
outermost of the sheets to define a lifting tab, a lead-in barrier
material bonded to the inner surface of the sheet that is severed
when the tear means is utilized, a liner formed from fluid
impervious material bonded to the inner surface of the container
and having a fixed hem composed of a section folded outwardly
through the inner butt joint and back upon the underlying sheet and
bonded to the underlying sheet material of the body wall, and a
bond between the outer surface of the fixed hem and the overlying
lead-in material, pulling a force exerted upon the lifting tab
toward the inner butt joint will be transmitted through the bond
between the fixed hem and the lead-in sheet to the underlying
portion of the container body thereby separating the adjacent parts
of the inner butt joint from one another, said bond between the
lead-in sheet and the fixed hem preventing the leakage of fluid
from the container.
10. The container according to claim 9, wherein the opposite end of
the liner is also folded outwardly through the inner butt joint
area and back upon itself to define a second hem, at least a
portion of the outer surface of the second hem being also bonded to
the overlying lead-in sheet to provide a substantially fluid-tight
seal for preventing the loss of materials from the container.
11. The container according to claim 9 wherein a pair of circular
end closure members are removably crimped to the ends of the tube
whereby the pulling of the lifting tab outwardly will cause the
edges that are crimped into the end closure members to be withdrawn
from the closure members as the container is opened to permit the
container to be opened in the area of the end closure members.
12. A pressure-retaining container for materials under pressure
comprising a tubular body wall, at least one end closure member
affixed to the end of the tube to form a bottom for the container
and said body wall having a line of separation extending from one
end of the container to the other for opening the container, said
body wall including in at least part of its circumference a pair of
overlapping sheets, a free-swinging panel connected between the
overlapping sheets and being secured to the innermost of the two
sheets at a point adjacent to the line of separation and extending
circumferentially therefrom between said sheets and having its end
furthest removed from the line of separation secured to the outer
of the two sheets to provide a free-swinging panel, lifting of the
outermost of the overlapping sheets and pulling outwardly thereupon
will cause the panel to swing away from the innermost sheet to
provide an expansion space into which the compressed material is
free to expand as the tab is pulled to prevent the container from
popping when opened.
Description
The present invention relates to packaging products and more
particularly to a can which is particularly useful for storing and
shipping unbaked refrigerated dough under pressure. The container
of this invention is, however, also useful for packaging materials
which exert no pressure.
A dough can is described in U.S. Pat. No. 3,214,078 which includes
a longitudinally extending lap joint with an adjacent tear tab.
Although this container is satisfactory for many applications, the
leakage of moisture, oil or gas into the space between the
overlapped walls is sometimes a serious problem and the extra
thickness of material at the lap joint presents a raw edge which is
unsightly. Moreover, the double thickness of the container wall in
the overlap area interferes with reliably crimping the metal can
ends onto the tubular can body.
Other containers evaluated in the development of the present
invention opened with a loud pop or had thin unsupported portions
of the liner or label extending beyond the side edges of the body
wall when the body material is rolled up upon itself in coil form
before being made into a tube. Such extensions can be easily
damaged.
It is, therefore, an object of this invention to provide a simply
constructed tubular container which includes an effective provision
for eliminating the leakage of material into the open space between
the overlapped layers of the body wall.
Another object of the invention is the provision of an improved
quick opening can for the packaging of refrigerated dough with a
longitudinally extending lap joint and a provision which allows the
overlapped and sealed area to be reduced in size thereby lessening
the tendency for the container to be out of round.
A further object of the invention is the provision of an improved
container suited for storing fresh dough and having an opening tab
including a longitudinally extending free marginal edge which can
be pulled circumferentially to open the container and in which the
length of the opening tab can be varied substantially without
changing the size of the overlap area between the inner and outer
plies of the container.
A further object of the invention is the provision of an improved
container of the type described in which the longitudinally
extending edges of the liner and label do not project beyond the
adjacent edges of the container body wall.
A further object of the invention is the provision of a can for
storing material under pressure with a provision that enables the
can to be opened without a loud popping noise.
A further object of the invention is the provision of an improved
container of the type described in which the body wall of the
container is essentially constant in thickness thereby allowing
sheet metal discs (can ends) to be reliably crimped to the cut ends
of the body wall.
Another object of the invention is the provision of an improved
pressure retaining container including a tubular body wall having a
longitudinally extending opening tab and a provision that enables
the body wall of the container to be withdrawn from the crimped
seam of the metal can end when the tab is pulled.
These and other more detailed and specific objects will become
apparent from the following description of the invention and
drawings wherein:
FIG. 1 is a perspective view of a can embodying the invention.
FIG. 2 is a side elevational view of the container of FIG. 1 with
the opening tab partially drawn back.
FIG. 3 is a semi-diagramatic transverse sectional view taken
through the stock material used for forming the tubular wall of the
container.
FIG. 4 is a transverse sectional view of the container during the
last stages of manufacture.
FIG. 5 is a view similar to FIG. 4 after the assembly of the body
wall has been completed.
FIG. 6 is a partial longitudinal sectional view of the end of the
container.
FIG. 7 is a partial transverse sectional view showing the first
stage in opening the container.
FIG. 8 is a view similar to FIG. 7 showing a subsequent stage of
opening, and
FIG. 9 is a view similar to FIG. 8 showing a later stage in the
opening procedure.
In the accomplishment of the above objectives, the invention then
comprises the features hereinafter fully described and particularly
pointed out in the claims, the following description setting forth
in detail certain illustrative embodiments of the invention, these
being indicative, however, of but a few of the various ways in
which the principles of the invention may be employed.
Briefly, the present invention provides a cylindrical can in which
the body wall is formed from at least two sheets each having four
edges. The sheets are preferably rectangular but any parallelogram
is suitable. The two sheets making up the body wall need not have
exactly the same shape. The sheets are bonded together with two
pairs of their corresponding edges out of alignment. In this way,
two generally longitudinally oriented extensions are provided. This
composite sheet is formed into a tube with extensions positioned in
overlapping relationship and adhered to one another to provide a
longitudinally extending bond defining inner and outer butt joints.
A provision is made for tearing the outer layer of the body wall
longitudinally along a tear line positioned at any point
circumferentially of the overlap area within 180.degree. and
preferably within 45.degree. of the overlap area. When the outer
layer is torn along this line, a pull tab is formed by the
longitudinally extending free edge adjacent the tear. When the pull
tab is lifted and pulled back toward the overlap area, the force
exerted from the outer extension is transmitted to the inner
extension through the permanent bond thereby separating the
adjacent edges of the inner butt joint from one another and
preferably withdrawing the ends of the body wall from their crimped
position in the can ends.
The container preferably includes a fluid impervious liner formed
from thin sheet material lying adjacent to the inner surface of the
body wall of the container. The liner is folded outwardly over
edges of the inner sheet that define the inner butt joint and lie
adjacent to its outer surface near the longitudinally extending
edge thereof. This flap of the liner is bonded to the overlying
material of the pull tab so that when the tab is used to open the
container, the flap will swing free of the underlying inner sheet
material to provide an expansion space for the dough.
The invention will now be described in detail with reference to the
figures.
As seen in the figures, the container indicated generally by the
numeral 10 comprises a can formed from a tubular body wall 12 and
sealed on each end by two identical circular metal end caps 11 and
13. The body wall 12 is formed from flexible sheet material 14
(FIG. 3) composed of a laminate consisting of two relatively thick
interior sheets 16 and 18. These sheets may be about 0.014 inches
thick and composed of paperboard. Sheets 16 and 18 are suitably
bonded to one another by an adhesive 20 which can be applied either
in selected areas or, if desired, over the entire contacting
surface. As seen in FIG. 3, the sheets 16 and 18 are positioned
relative to one another such that their side edges (longitudinally
extending edges when formed into a cylinder) are positioned out of
alignment so as to provide an internal extension 22 and an external
extension 24. The two remaining edges of the body wall 12, i.e.,
those that fit into the edges of the can ends 11 and 13 are
positioned in alignment with one another. Accordingly, it is only
the two longitudinally extending edges that are positioned out of
alignment with one another to provide the circumferentially
projecting inner extension 22 and the circumferentially projecting
extension 24.
A liner 26 which is formed from any of a variety of fluid
impervious materials such as a laminate composed of aluminum foil
bonded to Kraft paper is glued preferably over substantially the
entire exposed surface of the inner sheet 18. The liner 26
functions to prevent the penetration of water and grease from the
inside of the package into the paperboard layer 18.
A label 28 is preferably bonded to the exterior surface of the
sheet 16. If used, the label 28 can be formed from the same
material as the liner 26 and is normally printed with the name of
the product and directions for its preparation. When no label is
used, sheet 16 can be printed.
As best seen in FIGS. 3 and 4, the edges of neither the liner nor
label extend beyond the longitudinally disposed edges of the sheets
16 and 18. In the case of the label, its longitudinally disposed
edges terminate in alignment with the corresponding edges of the
outer sheet 16. The edge of the liner 26 adjacent to the extension
22 is folded outwardly and thence back upon the outer edge of the
extension 22 and is securely bonded to it by adhesive at 32 thereby
forming a longitudinally extending permanently secured hem 30.
The opposite end of the liner 26 is folded outwardly in a loose
manner and back upon the outer surface of the body sheet 18 to
provide a free hem 34 which is not bonded or otherwise fastened to
the adjacent surface 36 of the inner sheet 18.
Positioned between the sheets 16 and 18, adjacent to the outer
terminal extension 24 is a lead-in sheet 40 formed from a fluid
impervious material which may be the same as the liner and label.
It is securely bonded to sheet 16 by adhesive 42. As shown in FIG.
3, the free edge of the sheet 40 extends slightly beyond the free
edge of the inner body sheet 18. The opposite edge of the sheet 40
extends to a longitudinally extending tear means such as tape 44
which is bonded to the sheet 16 by means of adhesive 46. It will be
noted that the tear tape 44 is spaced circumferentially a distance
from the overlap of the extensions 22 and 24, i.e., it is outside
of the overlap area. Spacing between the overlap area and the tear
tape 44 can be as great as desired but should not be so short that
the fingers of the person opening the can come in contact with the
dough as it is expelled from the can at the time the can is
opened.
As clearly shown in FIGS. 3, 4 and 5, only the edge of the free hem
34 is bonded by a liquid tight seal 50 (e.g., a hot melt adhesive
seal formed by applying molten heat-sealing adhesive to the hem 34)
to the overlying lead-in sheet 40. Only the edge of the free hem 34
is adhered to the lead-in sheet 40 for reasons to be described
below.
As shown in FIGS. 1 and 2, a C-shaped cut 52 is provided at one end
of the tear tape 44 through the label 28 and outer sheet 16 of the
core to define a pull tab 54 at the leading edge of the tear tape
44.
The end caps or closures 11 and 13 each consist of a thin metal
disc removably crimped by means of seams 56 and 58 to the upper and
lower circular edges 15 and 17 respectively of the body wall 12.
After the bottom closure 11 has been applied, the biscuits are
placed in the container and the top closure 13 is applied and
crimped, in other words, seamed, at 58 in a conventional manner to
the upper circular edge 15 of the container 10.
As shown in FIGS. 4 and 5 which illustrate successive stages of
forming the body wall 12 into a tube, the outer extension 24 is
bonded in overlapping relationship to the inner extension 22 by
means of a permanent bond 60 of any suitable adhesive adapted to
keep the parts permanently bonded together. By "permanent" is meant
a bond which will not open when the container is opened. A
permanent bond is also made at 62 between the fixed hem 30 and the
overlying portion of the lead-in sheet 40. A relatively narrow
longitudinally extending peelable bond 50 is made between the edge
of the free hem 34 and the overlying lead-in sheet 40. The bond 50
functions to raise the hem 34 when the container is opened. In the
last stages of opening the bond 50 peels apart. Thus the bonds 50
and 62 provide a reliable grease and moisture barrier to prevent
the escape of material from the container even though the contents
are under considerable pressure while the bond 60 provides the
requisite strength for preventing separation of the overlapping
extensions 22 and 24.
Referring primarily to FIG. 3, a preferred method of fabricating
the package will now be described.
The stock used to make the container is assembled in accordance
with a preferred manufacturing procedure by bonding the pull tab 44
and the lead-in strip 40 to sheet 16. At the same time, the label
28 is bonded to the outer surface of sheet 16.
The liner 26 is glued to the undersurface of sheet 18 and both the
left- and right-hand edges thereof are folded upwardly and
centrally over the corresponding edges of sheet 18. The fixed him
30 is then bonded to the outer surface of the extension 22 with the
adhesive 32.
The resulting sheets are next glued together by adhesive designated
20. It will be noted that adhesive 20 does not extend at the right
to the tear tape 44 (FIG. 3). Accordingly, the portion of sheet 16
and 18 to the right-hand side thereof as seen in FIG. 3 are not
bonded together except by the narrow bond 50 between the liner 26
and the overlying lead-in tab 40. Excellent results have been
obtained when the bond 50 is formed by heat sealing. In this event,
the liner or the lead-in tab are coated with a heat sealing varnish
or resin. The bond 50 covers just the edge of the hem 34 as
mentioned above. The completed contour body 12 consists of a sheet
which is shown in transverse cross section in FIG. 3. It is
normally rolled up upon itself to form a large coil or storage roll
before being cut and formed into a tube.
The body wall 12 can be formed into a tube in any suitable known
manner as described, for example, in U.S. Pat. Nos. 3,213,890 and
3,139,012. The last stage of the tubing operation is shown in FIG.
4. At the stage shown in FIG. 4, the extension 24 is drawn toward
and placed in overlapping relationship with extension 22. The
longitudinally extending band of adhesive 60 securely bonds the
adjacent flaps together and provides a permanent connection between
them. When the edges of the tube are brought together, an external
longitudinal butt joint 80 and internal longitudinal butt joint 82
are formed.
The bond 62 is preferably formed at the same time as bond 60. The
bond 62 is preferably formed by heat sealing (in which event either
the inward surface of the lead-in tab 40 or the adjacent surface of
the liner 26 is covered with a heat sealing varnish or other
thermoplastic resin) or by extruding a hot melt adhesive into the
seam.
After the tube has been made and cut transversely at 15 and 17, the
circular metal end or bottom closure 13 is applied by removably
crimping its edges onto the adjacent end 17 of the container body
12. By "removably" is meant that the edges of the body wall are
capable of being removed (i.e., withdrawn) without being torn apart
when the container is opened and the tab 86 is pulled.
After the bottom closure 13 has been applied, the contents of the
package, e.g., pieces of biscuit dough 84 (FIG. 2), are inserted.
The dough normally contains a leavening material such as an acid
and a base in sufficient quantity to maintain the dough within the
container under pressure during its normal storage period.
The lid 11 is placed on the top of the container and its edges
removably crimped to the edge 15 of the container body 12.
The manner in which the package is opened will now be described
with particular reference to FIGS. 1, 2, 7, 8 and 9.
The tear tape 44 is first pulled from left to right as seen in
FIGS. 1, 2, 7, 8 and 9 by grasping the extension 54. Pulling the
tape 44 produces a longitudinally extending opening tab 86 which
the user then grasps with his fingers and pulls upwardly as seen in
FIG. 2. At the tab 86 is pulled open (toward the right as seen in
FIG. 5), the opening force is transmitted to the sheet 18 by means
of the permanent bond 60 and to some extent by the bond 62.
It should be noted that as the tab 86 is lifted, the unattached
portion of the free hem 34 pivots outwardly as a free swinging
panel since it is not adhered to the underlying body sheet 18. As
this is done, the pressurized dough is expelled through the opening
between the butt joint 82 into an expansion area 88. In this way,
the pressure of the dough is relieved without causing the container
to pop when opened.
Continued movement of the pull tab 86 toward the right as seen in
FIGS. 7, 8 and 9 will cause the liquid tight seal 50 to be broken.
Further movement of the tab 86 will slide the cut ends 15 and 17 of
the fiber body wall 12 from their tightly engaged position within
the seams 56 and 58. Because the thickness of the body wall is
approximately the same at all points around the circumference of
the container, the force required to withdraw the body wall from
the seams 56 and 58 is constant. Accordingly, the tube 12 can be
easily capped and readily opened.
The invention has a number of important advantages. The container
can be readily opened without the occurrence of a loud,
objectionable pop, and it is relatively easy to make a wide opening
in the container since the cut ends 15 and 17 slide out of the
seams 56 and 58. This allows those biscuits adjacent the metal
discs 11 and 13 to be readily removed.
It will also be seen that the liquid tight seals 50 and 62 prevent
the leakage of moisture, gas and oil in the interior of the
container through the butt joint 82 into the area between the
sheets of material from which the container wall is formed.
Moreover, no unsightly raw edge of the material exists at the lap
joint.
A further advantage of the invention is the elimination of
laterally extending unsupported portions of the liner or label
which, if present, can be easily damaged when the raw material for
the container body is stored in roll form.
A further advantage of the invention is the reduction in the width
of the overlap area. This is desirable because it tends to make the
container more exactly circular.
It is apparent that many modifications and variations of this
invention as hereinbefore set forth may be made without departing
from the spirit and scope thereof. The specific embodiments
described are given by way of example only and the invention is
limited only by the terms of the appended claims.
* * * * *