U.S. patent application number 10/375418 was filed with the patent office on 2004-04-15 for container.
Invention is credited to Alexander, Garold W., Fought, Michael R., Kauffman, Jason L..
Application Number | 20040069790 10/375418 |
Document ID | / |
Family ID | 32073012 |
Filed Date | 2004-04-15 |
United States Patent
Application |
20040069790 |
Kind Code |
A1 |
Alexander, Garold W. ; et
al. |
April 15, 2004 |
Container
Abstract
A container comprising a sidewall and an endwall connected by a
heat sealed joint. The endwall has, in an operable orientation, a
major upper surface, an endless, upwardly opening, peripheral
channel and a heat sealable, fluid barrier, surface layer adhered
to the major upper surface of the endwall. The sidewall has a heat
sealable, fluid barrier, surface layer adhered to its inner and
outer surfaces. The end of the sidewall is engaged and crimped
within the endwall channel with the surface layers of the sidewall
heat sealed to the surface layer of the endwall to form a sealed,
mechanically rigid joint.
Inventors: |
Alexander, Garold W.; (Lewis
Center, OH) ; Kauffman, Jason L.; (West Liberty,
OH) ; Fought, Michael R.; (Columbus, OH) |
Correspondence
Address: |
KREMBLAS, FOSTER, PHILLIPS & POLLICK
7632 SLATE RIDGE BOULEVARD
REYNOLDSBURG
OH
43068
US
|
Family ID: |
32073012 |
Appl. No.: |
10/375418 |
Filed: |
February 27, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60417331 |
Oct 9, 2002 |
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Current U.S.
Class: |
220/612 |
Current CPC
Class: |
B31B 50/60 20170801;
B65D 3/22 20130101; B31B 50/745 20170801; B65D 3/12 20130101; B31B
50/642 20170801; B31B 2105/0022 20170801 |
Class at
Publication: |
220/612 |
International
Class: |
B65D 006/28; B65D
008/04; B65D 008/06 |
Claims
1. A container comprising: a) an endwall having, in an operable
orientation, a major upper surface, an endless, upwardly opening,
peripheral channel and a heat sealable, fluid barrier, surface
layer adhered to the major upper surface of the endwall; and b) a
sidewall, having an inner surface, an outer surface, a heat
sealable, fluid barrier, surface layer adhered to at least one of
said sidewall surfaces, an end of the sidewall being engaged within
the channel with the surface layer of the sidewall heat sealed to
the surface layer of the endwall.
2. The container in accordance with claim 1 wherein the cross
sectional configuration of the sidewall and the peripheral
configuration of the endwall are identical geometrical shapes
selected from the group consisting of oval, square, rectangular,
triangular and trapezoidal.
3. The container in accordance with claim 1 wherein the sidewall
has a circular cross section and the endwall is circular.
4. The container in accordance with claim 1, wherein the endwall is
a paperboard sheet material.
5. The container in accordance with claim 3, wherein the sidewall
is a paperboard sheet material.
6. The container in accordance with claim 1, wherein the inner
surface of the sidewall has a heat sealable surface layer.
7. The container in accordance with claim 1, wherein the outer
surface of the sidewall has a heat sealable surface layer.
8. The container in accordance with claim 1, wherein both the outer
surface and the inner surface of the sidewall have a heat sealable
surface layer heat sealed to the endwall surface layer.
9. The container in accordance with claim 1, wherein the heat
sealable surface layer is polyethylene.
10. The container in accordance with claim 1, wherein the endwall
channel is crimped to seat the heat sealable surface layer at the
channel against the sidewall.
11. The container in accordance with claim 10, wherein the endwall
and the sidewall are a paperboard sheet material, wherein both the
outer surface and the inner surface of the sidewall have a heat
sealable surface layer heat sealed to the endwall surface
layer.
12. The container in accordance with claim 11, wherein the surface
layers are polyethylene.
13. The container in accordance with claim 12, wherein the sidewall
is cylindrical and the endwall is circular.
14. A method for forming a container, the method comprising: a)
forming an endless, peripheral channel in an endwall constructed of
a sheet material having, in an operable orientation, a major upper
surface and a heat sealable, fluid barrier, surface layer adhered
to the major upper surface and extending into the channel; b)
inserting a sidewall into engagement in the channel, the sidewall
having an inner surface, an outer surface, and a heat sealable,
fluid barrier, surface layer adhered to at least one of said
surfaces; c) crimping the endwall channel against the sidewall to
form a joint; and d) heating said joint to heat seal the heat
sealable layers of the endwall and the sidewall at the joint.
15. The method for forming a container in accordance with claim 14,
wherein the crimping and heating steps comprise: (a) heating a pair
of mating male and female dies, one die formed to engage an
inwardly facing wall of the channel and the other die formed to
engage an outwardly facing wall of the channel; and (b)
compressibly wedging the channel against the sidewall between the
dies to effect crimping and to transfer heat to the joint.
16. The method for forming a container in accordance with claim 15
further comprising supporting the endwall on a mandrel when the
channel is engaged with the sidewall.
Description
(e) BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to containers for
containing fluid materials, such liquids, powders and granular
materials and potentially fluid materials, such as ice cream, and
more specifically relates to the structure and method of joining
and sealing a container endwall, such as its bottom, to its
sidewall.
[0003] 2. Description of the Related Art
[0004] Containers for fluids often are made with a bottom endwall,
which is attached to a surrounding sidewall of the container. The
prior art has disclosed the use of fluid barriers, such as
polyethylene, as a film coated on fluid pervious wall material,
such as paperboard, in order to prevent absorption or leakage of
the fluid. Bulk ice cream is typically packaged in a three gallon
container having a cylindrical sidewall joined to a circular
endwall. Although ice cream is frozen solid in its normal state,
when it is warmed during use, some will become liquid. Ice cream or
any other substance which is, or may become, liquid must be
contained in a way in which leakage will not occur.
[0005] One part of such a container which is particularly subject
to leakage is the joint between the sidewall and the endwall. The
prior art has provided a variety of ways of sealing the joint
between the sidewall and the endwall. Some use a metal ring or an
entirely metal endwall, such as shown in U.S. Pat. No. 2,303,322,
in order to obtain a strong, durable crimp between the endwall and
sidewall. However, metal rings may cause contamination of the
product held within the container, if the product is for human
consumption. Metal endwalls or rings also may have exposed sharp
edges which can cause injury or damage and also make it more
difficult to inspect a contained product with a security device
such as a metal detector or x-ray device. These difficulties can
increase the cost of and/or delay the shipping or receiving of
products in this type of container. Additionally, a metal ring
presents an additional component to be assembled onto the container
and therefore increases the cost of assembly for companies which
assemble and fill containers.
[0006] Other prior art containers use a separate or additional
means for sealing the joint between the sidewall and the endwall.
Some, such as shown in U.S. Pat. Nos. 2,303,322 and 4,117,971 add a
fillet or seal by filling the interior of the joint with an
additional sealing material. This, however, requires the additional
manufacturing step, and its added expense, of applying the sealing
material, usually after the sidewall is joined to the endwall.
[0007] Still other prior art, such as U.S. Pat. No. 4,556,166, adds
a separate, additional sealing disk to seal the endwall to the
sidewall. Although effective, this also requires an additional
component to ship and handle and an additional manufacturing step
to assemble the container.
[0008] Not only is it important to construct a container so that it
is entirely fluid impervious, but it is also important that the
fluid impervious characteristics be maintained after the container
is subjected to the mechanical stress of retaining the contents and
of being subjected to handling during filling, shipping and use.
Thus, the mechanical strength of the joint between the sidewall and
endwall should be sufficiently strong that the fluid impervious
seal will not become broken.
[0009] As with most containers, it is also desirable that the cost
of manufacture be minimized so long as the above characteristics
are also maintained. Therefore, it is desirable that the number of
component structures to be assembled and the manipulative
operations required to assemble the container be minimized.
[0010] It is, therefore, an object of the invention to provide a
container structure that requires no manipulative step of forming
the sidewall to fit into the endwall, requires no separate
component part for sealing the sidewall to the endwall, requires no
metal components, and that still provides both a very good seal and
a strong mechanical connection between the sidewall and the
endwall.
[0011] A further object of the invention is to provide a container
structure which permits a minimum number of component parts to be
shipped to the manufacturer of the product to be filled into the
container, permits those parts to be shipped in a flat, nested
configuration in order to ship and store them in a compact form
thereby minimizing shipping and storage costs and permits the parts
to be assembled with a minimum of manipulative operations in order
to minimize costs.
(f) BRIEF SUMMARY OF THE INVENTION
[0012] The invention is a container comprising a sidewall and an
endwall connected by a heat sealed joint. The endwall has, in an
operable orientation, a major upper surface, an endless, upwardly
opening, peripheral channel for receiving and engaging the sidewall
and a heat sealable, fluid barrier, surface layer adhered to the
major upper surface of the endwall. The sidewall has an inner
surface, an outer surface and a heat sealable, fluid barrier,
surface layer adhered to at least one of said sidewall surfaces.
The end of the sidewall is engaged within the endwall channel with
the surface layer or layers of the sidewall heat sealed to the
surface layer of the endwall.
(g) BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0013] FIG. 1 is a view in side elevation of a container embodying
the present invention.
[0014] FIG. 2 is view in vertical section taken substantially along
the line 2-2 of FIG. 1 illustrating the sidewall and end wall of
the container of FIG. 1 before assembly.
[0015] FIG. 3 is view in vertical section taken substantially along
the line 2-2 of FIG. 1 illustrating the sidewall and end wall of
the container of FIG. 1 after assembly and heat sealing them
together.
[0016] FIG. 4 is an enlarged view showing in detail the unassembled
joint components of FIG. 2.
[0017] FIG. 5 is an enlarged view showing in detail the assembled
joint components of FIG. 3.
[0018] FIG. 6 is a view in vertical section illustrating the
preferred manner of crimping and heat sealing the endwall to the
sidewall of a container embodying the invention.
[0019] FIGS. 7 through 9 are views in vertical section sequentially
illustrating the assembly, crimping and heat sealing steps of the
invention.
[0020] In describing the preferred embodiment of the invention,
which is illustrated in the drawings, specific terminology will be
resorted to for the sake of clarity. However, it is not intended
that the invention be limited to the specific term so selected and
it is to be understood that each specific term includes all
technical equivalents, which operate in a similar manner to
accomplish a similar purpose.
(h) DETAILED DESCRIPTION OF THE INVENTION
[0021] FIG. 1 illustrates a container 10, which is a cylindrical
canister of the type commonly used for containing ice cream. The
container 10 has a cylindrical sidewall 12 and a circular endwall
14 enclosing its bottom end. A rim or ring 16, though not
necessary, may be frictionally engaged upon the top edge of the
sidewall 12 to receive a lid 18. FIG. 2 illustrates the sidewall 12
and endwall 14 prior to assembly and FIG. 4 illustrates a segment
of those two components in enlarged detail.
[0022] In its operable orientation when operating as a bottom, the
endwall 14 has a major upper surface 20 and an endless, upwardly
opening, peripheral channel 22. A heat sealable, fluid barrier,
surface layer 24 is adhered to the major upper surface 20 of the
endwall 14. Adhered, as used in the context of this description, is
directed to a film layer bonded to the paperboard of a principal
wall material, such as paperboard, regardless of how the fluid
impervious layer was formed there, for example by extrusion,
spraying or otherwise depositing a fluid impervious material to
form the layer in situ or by bonding a preformed film to the
surface of the sheet.
[0023] In the preferred embodiment, as an example of the invention,
the endwall 14 is formed of paperboard, and particularly 0.028"
caliper CNK. The fluid barrier surface layer 24 on the upper
surface 20 is preferably an extrusion coated layer of 0.75 mil, low
density polyethylene. Preferably the opposite surface of the
endwall 14 is coated with an aqueous Michelman coating PK910. This
coating is applied to prevent moisture penetration and to aid in
the thermoforming process used to form the channel. The upwardly
opening peripheral channel 22 is thermoformed by pressing an
initially circular disc around its edge, to form a channel having a
lengthwise contour which follows the contour of the end of the
later inserted sidewall. As will be seen, this permits the end edge
of the sidewall to extend into the channel and ultimately be
engaged by it. The invention is not limited to paperboard, but may
be applied to other materials, which have a heat sealable
layer.
[0024] The sidewall 12 has a heat sealable, fluid barrier, surface
layer 26 adhered to the inner surface of the sidewall 12, and a
similar surface layer 28 adhered or coated on the outer surface of
the sidewall 12. Although it is only necessary that the fluid
barrier surface layer be formed on only one of the surfaces of the
sidewall, preferably the interior surface, most preferably the
fluid barrier surface layer is formed on the interior and exterior
surfaces of the sidewall in order to maximize the moisture
resistance of the paperboard sidewall 12, maximize the seal between
the endwall 14 and the sidewall 12 and maximize the mechanical
strength of the connection of the endwall 14 to the sidewall 12.
The surface layers 26 and 28 on the sidewall are preferably formed
in the same manner and of the same material as the surface layer 24
on the endwall 14.
[0025] The container components illustrated in FIGS. 2 and 4 are
assembled into the container illustrated in FIG. 3 having the
detailed structure illustrated in FIG. 5. The sidewall 12 is moved
into engagement in the peripheral channel 22 formed around the
endwall 14. The peripheral channel 22 is then crimped against the
lower rim of the cylindrical sidewall 12 and the engaged lower rim
and channel are heated to heat seal together the fluid barrier,
surface layer 24 of the end wall 14 and the fluid barrier, surface
layers 26 and 28 of the sidewall 12, as illustrated in FIG. 5.
Because the single fluid barrier layer formed on the endwall is
heat sealed to both of the fluid barrier layers on the sidewall,
there is a double seal at this joint and both also contribute to
the mechanical strength and durability of the joint.
[0026] Containers embodying the invention are not limited to
cylindrical canisters. Containers may be made having a rectangular,
oval or other geometrical configurations. For example, an endwall
may be formed in an oval or rectangular polygon with a channel
around its peripheral edge to receive a sidewall having an end with
a cross-sectional shape contoured and sized to matingly engage
within the channel.
[0027] As another alternative, it is unnecessary to provide an
interior or exterior surface layer upon the entire surface of the
sidewall for purposes of the present invention. For example, for
purposes of the invention, the heat sealable, fluid barrier,
surface layer could be applied only around the lower surface area
of the sidewall, such as in a peripheral annular ring, where it can
engage the surface layer formed on the surface of the endwall
within the channel. However, although this can be done to provide
the joint seal, mechanical strength and other advantages of the
present invention, it is not preferred because the surface layer is
also desired over the entire inner surface of the sidewall, so that
it can provide its conventional, prior art fluid barrier
characteristic to the entire container. In a like manner, the
surface layer can be adhered on the endwall only within the endless
channel in order to provide the advantages of the invention, but
this too is not desired because it is preferable that the entire
endwall surface have a fluid barrier to accomplish its conventional
prior art purpose.
[0028] FIGS. 6-9 illustrate the preferred method for assembling the
endwall to the sidewall in order to form a container embodying the
present invention. Preferably they are assembled while in an
inverted orientation by supporting the sidewall 12 within a
circular groove 40, formed in a support platform 42. A mandrel 56
is supported on the support platform 42 and has a shape and size to
conform to and support the interior of the finished container. A
first die 44 is shaped to engage an inwardly facing wall 46 on the
exterior of the channel 22 formed around the endwall 14. A mating
die 48 supports the die 44 by means of springs 50. The mating die
48 has a surface 52 formed to engage an outwardly facing surface 54
of exterior of the channel 22.
[0029] The endwall 14 is assembled to the sidewall 12 by first
positioning the endwall 14 to sit upon the sidewall 12 so that the
sidewall 12 is inserted into the channel 22. The top of a mandrel
56 supports the endwall 14 when the channel 22 has been brought
into engagement with the sidewall 12. The dies 44 and 48 are then
lowered. The die 44 first engages the inwardly facing wall 46 on
the exterior of the channel 22 as illustrated in FIG. 6. This
sequence is illustrated in going from FIG. 7 to FIG. 8, in which
the sidewall 12 has been brought into engagement with the channel
22 and the die 44 engages the end wall 14.
[0030] The endwall channel 22 is then crimped against the sidewall
12 to form a joint, as illustrated in FIG. 9. This is accomplished
by lowering the die 48 so that the channel 22 is compressively
wedged against the sidewall by the dies 44 and 48 to affect the
crimping. Heat is applied to the exterior surfaces of the channel
22 so that the heat sealable surface layers or films deposited on
the engaging surfaces within the joint become heat sealed, i.e.
welded together. This may be accomplished with conventional
electrical resistance heaters, mounted in the dies 44 and 48 in the
vicinity of the joint, while the joint is being crimped and
compressibly wedged between the dies 44 and 48. The heat is
conducted from the dies to the engaged heat sealable materials. The
heat sealable layers become softened and melted, in the manner
known to those skilled in the art, so that they are bonded and/or
flow together.
[0031] From the above description, it is apparent that a container
embodying the present invention is easier to assemble because it
only requires one assembly step on the assembly machine instead of
the two steps for containers which utilize metal rings. The
structure of the invention also does not require any forming of the
sidewall, such as formation of a flange, channel or lip, to permit
it to be attached too the bottom. Instead the simple end edge of
the sidewall is inserted into and engaged with the channel of the
endwall.
[0032] The container parts can be shipped economically in bulk to
the end user, who will package a product in the container, because
the component parts can be stacked in a relatively flat
configuration. Therefore these parts can be compactly packaged for
shipment to the filler, who then assembles them as they are needed
to package the filler's product. The sidewall components can be
shipped and stored as a stack of planar sheets and are bent or
contoured into a cylindrical or other sidewall geometrical shape
when being assembled for filling. The endwall components, with the
channel already formed, are easily shipped and stored as a nested
stack.
[0033] Because of the strength of the heat sealed joint, the
invention is also able to make the use of metal rings or other
metal components unnecessary, thereby avoiding the problems
described above.
[0034] While certain preferred embodiments of the present invention
have been disclosed in detail, it is to be understood that various
modifications may be adopted without departing from the spirit of
the invention or scope of the following claims.
* * * * *