U.S. patent application number 12/169711 was filed with the patent office on 2010-01-14 for plastic container possessing improved top load strength and grippability.
This patent application is currently assigned to GRAHAM PACKAGING COMPANY, L.P.. Invention is credited to Richard K. Ogg.
Application Number | 20100006535 12/169711 |
Document ID | / |
Family ID | 41504187 |
Filed Date | 2010-01-14 |
United States Patent
Application |
20100006535 |
Kind Code |
A1 |
Ogg; Richard K. |
January 14, 2010 |
Plastic Container Possessing Improved Top Load Strength and
Grippability
Abstract
A plastic container includes a sidewall having an outer surface
and an inner surface that defines an interior space. The sidewall
is shaped so as to define a container neck, a main body portion and
a dome that may be substantially rectangular in transverse
cross-section. The dome has a lower and that is integral with the
main body portion and a shoulder at an upper end that is integral
with the container neck. The dome preferably includes at least one
longitudinally extending buttress column defined in the sidewall
that when viewed in transverse cross-section protrudes laterally
outwardly from adjacent portions of the sidewall in order to
enhance the strength of the container. The longitudinally extending
buttress column may extend along an entire length of the dome from
the main body portion to the container neck in order to further
enhance the strength of the container.
Inventors: |
Ogg; Richard K.;
(Littlestown, PA) |
Correspondence
Address: |
KNOBLE, YOSHIDA & DUNLEAVY
EIGHT PENN CENTER, SUITE 1350, 1628 JOHN F KENNEDY BLVD
PHILADELPHIA
PA
19103
US
|
Assignee: |
GRAHAM PACKAGING COMPANY,
L.P.
York
PA
|
Family ID: |
41504187 |
Appl. No.: |
12/169711 |
Filed: |
July 9, 2008 |
Current U.S.
Class: |
215/384 |
Current CPC
Class: |
B65D 23/102 20130101;
B65D 1/0223 20130101; B65D 79/005 20130101; B65D 2501/0036
20130101; B65D 2501/0027 20130101; B65D 2501/0081 20130101 |
Class at
Publication: |
215/384 |
International
Class: |
B65D 8/04 20060101
B65D008/04 |
Claims
1. A plastic container, comprising: a sidewall having an outer
surface and an inner surface, said sidewall being shaped to define
a container neck; a main body portion; and a dome that is
substantially rectangular in transverse cross-section, said dome
having a lower end that is integral with said main body portion and
a shoulder at an upper end that is integral with said container
neck, and wherein said dome includes at least one longitudinally
extending buttress column defined in said sidewall that when viewed
in transverse cross-section protrudes laterally outwardly from
adjacent portions of said sidewall, whereby the strength of said
container is enhanced.
2. A plastic container according to claim 1, wherein said at least
one longitudinally extending buttress column extends along an
entire length of said shoulder portion.
3. A plastic container according to claim 2, wherein said at least
one longitudinally extending buttress column further extends along
a part of said dome that does not define said shoulder portion.
4. A plastic container according to claim 2, wherein said at least
one longitudinally extending buttress column extends for an entire
length of said dome from said main body portion to said container
neck.
5. A plastic container according to claim 2, wherein at least a
portion of said longitudinally extending buttress column is tapered
in width so as to be narrower at an upper end that it is at a lower
end.
6. A plastic container according to claim 1, wherein said dome
comprises two of said longitudinally extending buttress columns,
and wherein said longitudinally extending buttress columns are
positioned on opposite sides of said dome and are symmetrically
opposed to each other.
7. A plastic container according to claim 6, wherein said dome
comprises front and rear surfaces and first and second side
surfaces that are narrower than said front and rear surfaces, and
wherein said two longitudinally extending buttress columns are
respectively positioned on said side surfaces.
8. A plastic container according to claim 1, wherein said
longitudinally extending buttress column is generally C-shaped as
viewed in transverse cross-section.
9. A plastic container according to claim 1, wherein said
longitudinally extending buttress column has an outer surface that
is substantially flat.
10. A plastic container according to claim 1, wherein said
longitudinally extending buttress column includes a first tapered
portion located at a lowermost end of said dome, said first tapered
portion having a relatively broad base at a lower end that is
adjacent to said main body portion of said container and being
tapered so as to narrow as it extends upwardly.
11. A plastic container according to claim 10, wherein said
longitudinally extending buttress column further includes a second
tapered portion that is located on said shoulder portion of said
dome, said second tapered portion being tapered so as to narrow as
it extends upwardly to an upper end that is adjacent to said neck
portion of said container.
12. A plastic container according to claim 11, wherein said
longitudinally extending buttress column further includes a central
portion that is integral and continuous with an upper end of said
first tapered portion and a lower end of said second tapered
portion.
13. A plastic container, comprising: a sidewall having an outer
surface and an inner surface, said sidewall being shaped to define
a container neck; a main body portion; and a dome having a lower
end that is integral with said main body portion and a shoulder at
an upper end that is integral with said container neck, and wherein
said dome includes at least one longitudinally extending buttress
column defined in said sidewall that when viewed in transverse
cross-section protrudes laterally outwardly from adjacent portions
of said sidewall, said at least one longitudinally extending
buttress column extending along an entire length of said dome from
said main body portion to said container neck whereby the strength
of said container is enhanced.
14. A plastic container according to claim 13, wherein at least a
portion of said longitudinally extending buttress column is tapered
in width so as to be narrower at an upper end that it is at a lower
end.
15. A plastic container according to claim 13, wherein said dome
comprises two of said longitudinally extending buttress columns,
and wherein said longitudinally extending buttress columns are
positioned on opposite sides of said dome and are symmetrically
opposed to each other.
16. A plastic container according to claim 13, wherein said
longitudinally extending buttress column is generally C-shaped as
viewed in transverse cross-section.
17. A plastic container according to claim 13, wherein said
longitudinally extending buttress column has an outer surface that
is substantially flat.
18. A plastic container according to claim 13, wherein said
longitudinally extending buttress column includes a first tapered
portion located at a lowermost end of said dome, said first tapered
portion having a relatively broad base at a lower end that is
adjacent to said main body portion of said container and being
tapered so as to narrow as it extends upwardly.
19. A plastic container according to claim 18, wherein said
longitudinally extending buttress column further includes a second
tapered portion that is located on said shoulder portion of said
dome, said second tapered portion being tapered so as to narrow as
it extends upwardly to an upper end that is adjacent to said neck
portion of said container.
20. A plastic container according to claim 19, wherein said
longitudinally extending buttress column further includes a central
portion that is integral and continuous with an upper end of said
first tapered portion and a lower end of said second tapered
portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to plastic
containers, such as the plastic containers that are commonly used
to package beverages and other liquids.
[0003] 2. Description of the Related Technology
[0004] Many products that were previously packaged using glass
containers are now being supplied in plastic containers, such as
containers that are fabricated from polyesters such as polyethylene
terephthalate (PET).
[0005] PET containers are lightweight, inexpensive, recyclable and
can be economically manufactured in large quantities. PET therefore
possesses excellent characteristics for containers, but PET resin
is relatively expensive. Accordingly, a PET container design that
reduces the amount of material that is used without sacrificing
performance will provide a significant competitive advantage within
the packaging industry.
[0006] PET containers are typically manufactured using the stretch
blow molding process. This involves the use of a preform that is
injection molded into a shape that facilitates distribution of the
plastic material within the preform into the desired final shape of
the container. The preform is first heated and then is
longitudinally stretched and subsequently inflated within a mold
cavity so that it assumes the desired final shape of the container.
As the preform is inflated, it takes on the shape of the mold
cavity. The polymer solidifies upon contacting the cooler surface
of the mold, and the finished hollow container is subsequently
ejected from the mold.
[0007] PET containers are particularly common for use in packaging
beverages such as juices using what is known in the industry as the
hot-fill process. This involves filling the containers while the
liquid product is at an elevated temperature, typically 68.degree.
C.-96.degree. C. (155.degree. F.-205.degree. F.) and usually about
85.degree. C. (185.degree. F.) in order to sterilize the container
at the time of filling. Containers that are designed to withstand
the process are known as "hot fill" or "heat set" containers. Hot
fill containers must be designed to be strong enough in the areas
outside of the vacuum panel regions so that the deformation that
occurs as a result of the volumetric shrinkage of a product within
the container is substantially limited to the portions of the
container that are designed specifically to accommodate such
shrinkage. In addition, since filled containers are often stacked
on top of one another for transportation and distribution, the
sidewall of such containers must be designed to have sufficient
column strength in order to endure a predetermined minimum vertical
load. It is important that such column strength not be degraded as
the shape of the container changes as result of volumetric
shrinkage within the container.
[0008] The dome is the upper portion of the container adjacent the
finish. Some dome configurations are designed to have a transverse
cross-section which is generally circular in shape or
"bell-shaped". Other dome configurations are designed to possess a
transverse cross-section that is substantially rectangular in
shape. Both types of dome configurations may have a rounded upper
shoulder portion near the container neck. The diameter of the
transverse cross-section through a dome will typically increase as
the dome extends downwardly from the container neck or finish
portion. In some containers, the dome diameter then decreases to an
inwardly extending peripheral waist, and downwardly from the waist,
the dome diameter increases before connecting with the label
mounting area or main body portion of the container.
[0009] In many container designs, the dome is the weakest link in
terms of the column strength of the container. In order to minimize
material costs, desirable to make the sidewall of the container
dome, as with the rest of the container, as thin as possible.
However, such lightweighting comes at the expense of container
strength, and in particular column strength. Efforts have been made
to reinforce some types of container domes in order to enhance
their strength. For example, U.S. Pat. No. 5,222,615 issued to Ota
et al. discloses a container having a rectangular, horizontal
cross-section with a dome and support panels to increase the
strength of the container and compensate for unequal stretching of
the container during blow-molding. Another known container that
incorporates a degree of dome reinforcement is U.S. Pat. No.
5,067,622 issued to Garver et al., which discloses a hot-fillable
PET container having support panels located below the waist of its
bell-shaped dome to accommodate deformation due to the vacuum
effect caused by hot-filling. U.S. Pat. No. 5,310,068 issued to
Saghri discloses a collapsible container having panels spaced along
the periphery of its dome. U.S. Pat. Nos. 5,238,129 and 5,178,290
issued to Ota et al.; 4,805,788 issued to Akiho; 5,199,588 issued
to Hayashi; 4,946,053 issued to Conrad; and 4,818,575 issued to
Hirata et al. also disclose the use of panels in the dome portion
of a container.
[0010] However, many such designs insufficiently augment the column
strength of the container. In addition, the prior art designs in
many cases are not effectively applicable to dome configurations
that possess a transverse cross-section that is substantially
rectangular in shape. Moreover, many of these prior art designs are
aesthetically unattractive.
[0011] A need exists for an improved domed container that possesses
optimal column strength that is particularly suitable for use with
containers that possess a transverse cross-section that is
substantially rectangular in shape, and that is aesthetically
attractive.
SUMMARY OF THE INVENTION
[0012] Accordingly, it is an object of one facet of the invention
to provide an improved domed container that possesses optimal
column strength.
[0013] It is an object of another facet of the invention to provide
an improved domed container that is particularly suitable for use
with domed containers that possess a transverse cross-section that
is substantially rectangular in shape.
[0014] It is an object of yet another facet of the invention to
provide an improved domed container that is aesthetically
attractive.
[0015] In order to achieve the above and other objects of the
invention, a plastic container according to a first aspect of the
invention includes a sidewall having an outer surface and an inner
surface, the sidewall being shaped to define a container neck; a
main body portion; and a dome that is substantially rectangular in
transverse cross-section, the dome having a lower end that is
integral with the main body portion and a shoulder at an upper end
that is integral with the container neck, and wherein the dome
includes at least one longitudinally extending buttress column
defined in said sidewall that when viewed in transverse
cross-section protrudes laterally outwardly from adjacent portions
of the sidewall, whereby the strength of said container is
enhanced.
[0016] According to a second aspect of the invention, a plastic
container may include a sidewall having an outer surface and an
inner surface, the sidewall being shaped to define a container
neck; a main body portion; and a dome having a lower end that is
integral with the main body portion and a shoulder at an upper end
that is integral with the container neck, and wherein the dome
includes at least one longitudinally extending buttress column
defined in the sidewall that when viewed in transverse
cross-section protrudes laterally outwardly from adjacent portions
of the sidewall, the at least one longitudinally extending buttress
column extending along an entire length of the dome from the main
body portion to said container neck whereby the strength of the
container is enhanced.
[0017] These and various other advantages and features of novelty
that characterize the invention are pointed out with particularity
in the claims annexed hereto and forming a part hereof. However,
for a better understanding of the invention, its advantages, and
the objects obtained by its use, reference should be made to the
drawings which form a further part hereof, and to the accompanying
descriptive matter, in which there is illustrated and described a
preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a perspective view of a container that is
constructed according to a preferred embodiment of the
invention;
[0019] FIG. 2 is a front elevational view of the container that is
depicted in FIG. 1;
[0020] FIG. 3 is a cross-sectional view taken along lines 3-3 in
FIG. 2;
[0021] FIG. 4 is a cross-sectional view taken along lines 4-4 in
FIG. 2;
[0022] FIG. 5 is a cross-sectional view taken along lines 5-5 in
FIG. 2; and
[0023] FIG. 6 is a cross-sectional view taken along lines 6-6 in
FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0024] Referring now to the drawings, wherein like reference
numerals designate corresponding structure throughout the views,
and referring in particular to FIG. 1, a plastic container 10 that
is constructed according to a preferred embodiment of the invention
is preferably fabricated from a plastic material such as
polyethylene terephthalate (PET) using the well-known stretch blow
molding process. Alternatively, plastic container 10 could be
fabricated from the material such as polyethylene or polyolefin
using an extrusion blowmolding process, or other processes as are
well known in the industry.
[0025] Plastic container 10 in the preferred embodiment is a hot
fill type container, although the invention has applicability for
containers that are not of the hot fill type.
[0026] Plastic container 10 includes a sidewall 12 having an outer
surface and an inner surface that defines an interior space in
which a product such as a beverage or any one of a multiplicity of
different types of liquids or solids may be packaged. The sidewall
12 is shaped so as to define a container neck 14, which in the
illustrated embodiment is configured as a threaded finish portion
that is adapted to receive an internally threaded closure. A
sidewall 12 is further shaped so as to define a main body portion
16 that forms a bottom and a lower end of the plastic container 12.
The main body portion 16 in the illustrated embodiment includes a
relatively flat or slightly convexly curved label panel 18 that is
provided with a plurality of horizontally oriented reinforcing ribs
20. Main body portion 16 further includes a pair of side vacuum
panels 22 in which a plurality of horizontally oriented reinforcing
ribs 24 are provided. Main body portion 16 is configured so that it
is substantially rectangular in transverse cross-section.
[0027] Plastic container 10 is configured as a domed container, and
includes a dome portion 26 that in the preferred embodiment is
substantially rectangular in transverse cross-section. Dome portion
26 accordingly has front and rear surfaces 52, 54 and side surfaces
56, 58 that are smaller than the front and rear surfaces 52, 54. In
the preferred embodiment, the front and rear surfaces 52, 54 are
provided with gripping indentations 30 that are shaped so as to
enable a consumer to securely grip the plastic container 10 using a
pinching action with the thumb and forefinger. The gripping
indentations 30 are preferably positioned so that their adjacent to
the lower end 34 of the dome portion 26. The front and rear
surfaces 52, 54 also preferably include a display area 32 in which
some type of a display pattern such as a manufacturer's logo or
trademark may be embossed. The display area 32 is preferably
relatively flat and is preferably located in an intermediate
portion of the container dome 26 between the gripping indentation
30 and an upper shoulder portion 38 of the container dome 26.
[0028] The dome portion 26 has a lower end 34 that is integral with
the main body portion 16 and the aforementioned shoulder 38 at an
upper end 36 that is integral with the container neck 14. A
narrowed waist portion 28 may be provided between the dome portion
26 and the main body portion 16. The shoulder 38 preferably has an
outer surface that is slightly convex, and is tapered so that its
transverse cross-sectional area becomes reduced as it transitions
upwardly to the interface with the container neck 14.
[0029] One particularly advantageous feature of the plastic
container 10 is that includes at least one longitudinally extending
buttress column defined in the sidewall of the container dome 26
that when viewed in transverse cross-section protrudes laterally
outwardly from adjacent portions of the sidewall, thereby enhancing
the strength of the container 10. In the preferred embodiment,
plastic container 10 includes a pair of longitudinally extending
buttress columns 40, 42, which are provided respectively on the
side portions 58, 56 of the plastic container 10. Longitudinally
extending buttress columns 40, 42 are preferably symmetrically
opposed to each other and are further preferably symmetrical in
shape in order to provide symmetric reinforcement of the column
strength of the plastic container 10.
[0030] Preferably, both of the buttress columns 40, 42 extend along
an entire length of the shoulder portion 38. More preferably, both
of the buttress columns 40, 42 also extend along a part of the
container dome 26 that does not define the shoulder portion 38. In
the illustrated preferred embodiment, both of the buttress columns
40, 42 extend for an entire length of the container dome 26 from
the interface with the main body portion 16 upwardly to the
interface with the container neck 14.
[0031] Preferably, at least a portion of both of the buttress
columns 40, 42 is tapered in width so as to be narrower at an upper
end than it is at a lower end. In the illustrated embodiment, both
of the buttress columns 40, 42 include a first tapered portion 46
that is located near a lowermost end 34 of the container dome 26
and has a relatively broad base of a lower end that is adjacent to
the main body portion 16 and is tapered so as to narrow as it
extends upwardly. Both of the buttress columns 40, 42 in the
illustrated embodiment further include a second tapered portion 48
that is located on the shoulder portion 38 of the container dome 26
and that is tapered so as to narrow as it extends upwardly to an
upper end that is adjacent to the container neck 14. The
illustrated buttress columns 40, 42 further include a central
portion 50 that is integral in continuous with an upper end of the
first tapered portion 46 and a lower end of the second tapered
portion 48.
[0032] Preferably, the longitudinally extending buttress columns
40, 42 are configured to have the pleasing aesthetic appearance of
discrete bands or belts that extend longitudinally along the narrow
sides 56, 58 of the plastic container 10 upwardly, traversing the
shoulder portion 38 to the interface between the container dome 26
and the container neck 14. The buttress columns 40, 42 are unitary
portions of the sidewall that defines the shape of the plastic
container 10 and preferably have sidewall thickness that is not
substantially different than the sidewall thickness of the rest of
the container dome 26.
[0033] The buttress columns 40, 42 are preferably shaped so as to
be generally C-Shaped as viewed in transverse cross-section, and
have broad outer surface 44 that is substantially flat, although it
might have a slight convexity.
[0034] FIG. 3 is a cross-sectional view taken along lines 3-3 in
FIG. 2, showing a transverse cross-sectional profile of an extreme
lower end of the container dome 26.
[0035] FIG. 4 is a cross-sectional view taken along lines 4-4 in
FIG. 2, showing a transverse cross-sectional profile of a portion
of the container dome 26 that is not within the shoulder portion 38
but is slightly above the area that is depicted by FIG. 3. As may
be seen in FIG. 4, the buttress columns 40, 42 in this location
have a width W1 and a depth D1. Preferably, a ratio of the width W1
to the depth D1 is in this area is preferably within a range of
about 10:1 to about 4:1. The width W1 in this area is preferably
within a range of 20% to about 60% of the entire width WC of the
side portions 56, 58 of the container 10. The depth D1 is in this
area is preferably within a range of about 2 mm to about 4 mm, and
the width W1 in this area is preferably within a range of about 20
mm to about 60 mm.
[0036] FIG. 5 is a cross-sectional view taken along lines 5-5 in
FIG. 2, showing a transverse cross-sectional profile of a portion
of the container dome 26 that is not within the shoulder portion 38
but is slightly above the area that is depicted by FIG. 4. As may
be seen in FIG. 5, the buttress columns 40, 42 in this location
have a width W1 and a depth D1. Preferably, a ratio of the width W1
to the depth D1 is in this area is preferably within a range of
about 10:1 to about 4:1. The width W1 in this area is preferably
within a range of 20% to about 60% of the entire width WC of the
side portions 56, 58 of the container 10. The depth D1 is in this
area is preferably within a range of about 2 mm to about 5 mm, and
the width W1 in this area is preferably within a range of about 20
mm to about 50 mm.
[0037] FIG. 6 is a cross-sectional view taken along lines 6-6 in
FIG. 2, showing a transverse cross-sectional profile of a portion
of the container dome 26 that is within a lower part of the
shoulder portion 38 and is slightly above the area that is depicted
by FIG. 5. As may be seen in FIG. 6, the buttress columns 40, 42 in
this location have a width W1 and a depth D1. Preferably, a ratio
of the width W1 to the depth D1 is in this area is preferably
within a range of about 10:1 to about 4:1. The width W1 in this
area is preferably within a range of 20% to about 60% of the entire
width WC of the side portions 56, 58 of the container 10. The depth
D1 is in this area is preferably within a range of about 2 mm to
about 5 mm, and the width W1 in this area is preferably within a
range of about 20 mm to about 40 mm.
[0038] It is to be understood, however, that even though numerous
characteristics and advantages of the present invention have been
set forth in the foregoing description, together with details of
the structure and function of the invention, the disclosure is
illustrative only, and changes may be made in detail, especially in
matters of shape, size and arrangement of parts within the
principles of the invention to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *