U.S. patent application number 13/989869 was filed with the patent office on 2013-09-26 for container, container blank, and method of manufacture.
The applicant listed for this patent is Ian Darby, Mike D. Rodgers. Invention is credited to Ian Darby, Mike D. Rodgers.
Application Number | 20130248540 13/989869 |
Document ID | / |
Family ID | 45446078 |
Filed Date | 2013-09-26 |
United States Patent
Application |
20130248540 |
Kind Code |
A1 |
Darby; Ian ; et al. |
September 26, 2013 |
CONTAINER, CONTAINER BLANK, AND METHOD OF MANUFACTURE
Abstract
This invention provides a self-supporting container (10; 110;
210; 310) having at least one wall (36; 336), a base (52; 152; 252;
352) and a top (50; 350). The top has a closable spout (54) whereby
the container is suitable for storing and transporting materials
such as a drinks and other liquids. The wall is made of plastics
material and includes at least one wall air chamber (26; 226; 326).
The base has at least one base air chamber (84, 86), the at least
one base air chamber having a dimension (2d) which is greater than
a dimension (w) of the base whereby the base of the container is
concave. The concave shape of the base makes the container more
stable in use. There is also provided a blank for making the
container, and a method of manufacturing the container blank.
Inventors: |
Darby; Ian; (Earl Shilton,
GB) ; Rodgers; Mike D.; (Rugby, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Darby; Ian
Rodgers; Mike D. |
Earl Shilton
Rugby |
|
GB
GB |
|
|
Family ID: |
45446078 |
Appl. No.: |
13/989869 |
Filed: |
November 24, 2011 |
PCT Filed: |
November 24, 2011 |
PCT NO: |
PCT/GB11/52313 |
371 Date: |
May 28, 2013 |
Current U.S.
Class: |
220/635 ;
229/5.5; 493/162 |
Current CPC
Class: |
B65D 37/00 20130101;
B65D 25/00 20130101; B65D 75/5877 20130101; B65D 81/3893
20130101 |
Class at
Publication: |
220/635 ;
229/5.5; 493/162 |
International
Class: |
B65D 25/00 20060101
B65D025/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 29, 2010 |
GB |
1020123.4 |
Oct 18, 2011 |
GB |
1117963.7 |
Claims
1. A self-supporting container having at least one wall, base and a
top, the top having a closable spout, the wall being made of
plastics material and including at least one wall air chamber, the
base having at least one base air chamber, said at least one base
air chamber having a dimension which is greater than a dimension of
the base whereby the base of the container is concave.
2. A self-supporting container according to claim 1 in which the
base has a bottom chamber the bottom chamber being connected to the
at least one wall air chamber and to the at least one base air
chamber, the bottom chamber surrounding the at least one base air
chamber.
3. A self-supporting container according to claim 1 in which the
container is substantially rectangular in plan view, with four
walls.
4. A self-supporting container according to claim 3 in which there
is one wall air chamber defining each of the four corners of the
container.
5. A self-supporting container according to claim 1 in which the
spout is part of a spout assembly with a first passageway adapted
to permit material to be introduced into and removed from the
container and a valve for inflating the at least one air
chamber.
6. A self-supporting container according to claim 1 in which the is
made of a two-layer material, the spout having a passageway to
permit material to be introduced into and removed from the
container and a base plate surrounding the passageway, the base
plate being located between parts of each layer of material in the
top of the container.
7. A self-supporting container according to claim 1 in which the
wall, the base, the top and the spout are made from the same
plastics material.
8. A self-supporting container according to claim 1 having
deflating means.
9. A self-supporting container according to claim 1 having four
walls, the base and the top being substantially rectangular, the
container having fold lines whereby to define the form of the
container when collapsed, there being at least one fold line an
opposing pair of walls whereby the opposing walls are folded
inwardly in the collapsed container.
10. A self-supporting container according to claim 1 in which all
of the air chambers are connected together in a single air
network.
11. A self-supporting container according to claim 1 in which the
at least one wall air chamber and the base air chamber define a
first network comprising interconnected air chambers, the walls of
the container comprising a separate second air network.
12. A self-supporting container according to claim 11 in which the
pressure within the first air network is greater than the pressure
within the second air network.
13. A blank for making a container according to claim 1, the blank
comprising two layers of plastics material formed with seams
joining the layers together, the seams defining the air chambers
and also defining regions between the air chambers, all of the air
chambers being interconnected.
14. A blank for making a container according to claim 11, the blank
comprising two layers of plastics material formed with seams
joining the layers together, the seams defining the air chambers
and also defining regions between the air chambers, the air
chambers forming two separate air networks.
15. (canceled)
16. A method of manufacturing a container comprising the steps of:
providing a first layer of wall material; forming an opening
through the layer to define a fill opening; fixing a base plate of
a substantially rigid spout to the first layer, the spout having a
passageway, the passageway being substantially aligned with the
opening; providing a second layer of wall material; laying the
second layer of wall material over the first layer of wall
material, the second layer of wall material having an opening to
surround the passageway; fixing the second layer of material to the
base plate of the spout whereby the spout is secured between the
two layers; and fixing the first layer and the second layer
together.
17. The method according to claim 16 in which the first layer and
the second layer are fixed together by way of a number of seams,
the seams also defining air chambers within between the layers.
18. The method according to claim 16 in which the spout also
includes a valve, the spout defining a passageway for air to pass
through the valve and between the layers.
19. A method according to claim 17 in which the seams are formed by
a welding operation
20. A self-supporting container substantially rectangular in plan
view having four walls, a base and a top, the top having a closable
spout, the wall being made of plastics material wall air chambers
defining each of the four corners of the container, the base having
at least one base air chamber, said at least one base air chamber
having a dimension which is greater than a dimension of the base
whereby the base of the container is concave, in which the base has
a bottom chamber, the bottom chamber being connected to the at
least one wall air chamber and to the at least one base air
chamber, the bottom chamber surrounding the at least one base air
chamber, the spout having a passageway adapted to permit material
to be introduced into and removed from the container and a valve
inflating the at least one air chamber, the top being made of a
two-layer material, a base plate surrounding the passageway, the
base plate being located between parts of each layer of material in
the top of the container.
21. A self-supporting container according to claim 20 additionally
having deflating means.
Description
FIELD OF THE INVENTION
[0001] This invention relates to a container, to a container blank,
and to a method of manufacturing the container. The invention
relates in particular to a self-supporting closed container.
[0002] The container is expected to have is primary utility for
containing liquids such as beverages during their transportation
and storage, and the following description will therefore relate
primarily to such applications. However, the use of the container
for some solids (such as granular solids) is not excluded.
[0003] Directional and orientational terms such as "top" "bottom"
"base" and "vertical", for example, refer to the container in its
normal orientation of use, as shown in FIGS. 2 and 3, unless
otherwise stated.
BACKGROUND TO THE INVENTION
[0004] Many different containers are available, some of which are
open-topped. Examples of open-topped containers are disclosed in
U.S. Pat. Nos. 4,585,755, 5,135,132 and 5,314,250. Each of those
containers is self-supporting and derives some of its structural
strength from one or more chambers which are filled with air.
[0005] The present invention is directed to a closed container,
i.e. a container which can fully enclose a material such as a
liquid. Unless otherwise stated, the word "container" used in the
remainder of this application refers to a closed container rather
than an open-topped container such as those described in the above
patents.
[0006] With containers for liquids in particular, it is desirable
that the containers are sufficiently rigid to be self-supporting,
i.e. they do not collapse under their own weight when empty, or
under the weight of the liquid when full.
[0007] Some containers obtain at least some of their structural
strength from the contained product, so that the containers are not
self-supporting. Gelatinous liquids such as soups for example are
often supplied within a pouch having a front wall, a rear wall and
a base. The material from which the walls are made is of flexible
plastics, and the material is sufficiently thick to allow the
container to stand up when full of the soup. The material is not
sufficiently thick to support its own weight when empty, however.
Such containers are therefore not suitable for materials which may
be consumed over a period of time, for example fruit juices or
milk, for which the container should be self-supporting, i.e.
sufficiently rigid to stand up regardless of the volume of product
contained.
[0008] Other containers are made from aluminium and glass, and
whilst these containers are self-supporting they are not
universally acceptable. Aluminium containers in particular are not
preferred since they are not readily resealable, so that the
contained material may not retain its optimum freshness once the
container has been opened. Glass containers are self-supporting and
can be resealable, but are typically too heavy for more widespread
use. Both aluminium and glass containers must be transported empty
from the container manufacturer to the product supplier, and that
represents an oncost since the transporting vehicle will typically
not be fully utilised.
[0009] The weight of packaging is a factor in the cost of the
product to the eventual customer. The weight of the packaging
directly affects the cost of transportation, both from the
container manufacturer to the product supplier, and from the
product supplier to the retailer or customer. The product supplier
will typically seek to reduce the weight of the packaging, and will
also typically seek to avoid the under-utilisation of the vehicle
delivering the empty containers.
[0010] With wine, beer and other relatively expensive products, the
additional cost due to the weight of the packaging and the
under-utilisation of a transporting vehicle is not usually
significant, and so aluminium and glass containers continue to be
widely used. With other relatively less expensive products, and
products which are particularly price-sensitive such as milk and
fruit juices on the other hand, these additional costs are
significant, and the suppliers of these products, and the retailers
of these products, will usually seek to reduce the weight of the
packaging, and also to avoid any unnecessary oncost due to
under-utilisation of transport vehicles.
[0011] The use of plastics and combinations of paper and plastics
for the packaging of certain materials (including milk and fruit
juices) has therefore become increasingly widespread.
[0012] A commonly-used self-supporting container for fruit juices
is made of carton board (such as that sold under the trade name
"Tetra Brik".RTM. for example). A carton board container comprises
a vessel having a square cross-section in plan view with walls
comprising a number of layers of different materials. Most of the
structural strength is provided by a layer of card. The card is
made waterproof by at least one layer of plastics. One or more
additional layers are provided for specific purposes, for example a
metallic layer to prevent the passage of oxygen through the wall
whereby the shelf-life of the product is extended.
[0013] Carton board containers are particularly beneficial in terms
of space utilisation during transportation. Firstly, the container
can be made and delivered to the user in a collapsed, substantially
flat, condition, and it can be erected before being filled.
Secondly, the filled container can be stacked alongside other
similar containers during delivery to the retailer or customer,
with relatively little wasted volume.
[0014] Despite their advantages and widespread utilisation, carton
board containers have a number of disadvantages. Firstly, they are
necessarily made from a number of layers of different materials,
which makes recycling a used container more difficult. Whilst many
local authorities accept used carton board containers for
recycling, they are rarely if ever separated into their primary
components so that those components can be reused.
[0015] In addition, the product supplier is required to have a
dedicated machine to erect the container, the machine undertaking
the necessary folding and gluing operations. The machine is
necessarily complex and any breakdown may require the services of a
dedicated technician as the machine may be significantly different
to the other machines at the supplier's location.
[0016] Self-supporting plastics containers are commonly used for
liquids such as water and milk. Plastics containers are often used
where oxygen migration is not a significant concern, and so these
containers typically do not utilise a metallic layer. PE and PET
are commonly used material for plastics containers of this type. It
is not, however, typical to make the container lid from PET, so
that the lids of PET containers in particular must be recycled
separately from the remainder of the container.
[0017] Self-supporting containers which obtain some of their
structural strength from air-filled chambers are described in WO
2009/021329, U.S. Pat. No. 2,751,953, WO 80/02545, and also GB 2
333 085.
SUMMARY OF THE INVENTION
[0018] The inventors have appreciated that a new container is
required which seeks to avoid or reduce the above-stated
disadvantages of the various known containers and is particularly
(but not exclusively) suitable for use with liquids such as milk
and fruit juices. The inventors have also sought to provide a
container which weighs no more than, and ideally weighs less than,
the known containers of similar volume.
[0019] According to the first aspect of the present invention,
there is provided a self-supporting container having at least one
wall, a base and a top, the top having a closable spout, the wall
being made of plastics material and including at least one wall air
chamber, the base having at least one base air chamber, said at
least one base air chamber having a dimension which is greater than
the dimension of the base whereby the base of the container is
concave.
[0020] In the present invention it is the air within the wall air
chamber and the base air chamber which provides the structural
strength necessary for the container to be self-supporting.
Accordingly, when the container is empty the air chamber(s) can
also be empty, whereupon the container is not self-supporting and
can be collapsed for transportation, whereby the utilisation of the
transportation vehicle can be maximised.
[0021] The provision of at least one base air chamber having a
dimension which is greater than the dimension of the base creates a
base with an "over-centre" feature, i.e. a tendency to be concave
or convex rather than flat. It can be arranged that the filling
machine ensures that the base is concave, whereby the erected
container rests upon the periphery of its base rather than the
whole of its base, and is thereby more stable.
[0022] Preferably, the container is substantially rectangular
(ideally square) in plan view, with four walls. Preferably there is
one wall air chamber, or there are two wall air chambers, defining
each of the four corners of the container. More than two wall air
chambers can be used at each corner if desired, but that is
expected to be disadvantageous. Specifically, embodiments utilising
a single air chamber at each corner have the additional advantage
of increasing the available area of each of the walls of the
container which is suitable for the application of printed labels
and product information.
[0023] According to a second aspect of the invention, there is
provided a self-supporting container having at least one wall, a
base and a top, the top having a closable spout, the wall being
made of plastics material and including a plurality of air
chambers, the container having means to permit the deflation of
some of the air chambers during emptying of the container.
[0024] Embodiments of the invention according to the second aspect
have advantages as containers for use with particular industrial
materials. With some industrial materials it is desirable to avoid
the material coming into contact with air. The containers for those
materials are usually emptied by the application of a reduced
(vacuum) pressure applied to the container spout. The container is
designed to collapse as its contents are transferred to a machine
for subsequent processing. It is, however, a known concern that the
collapsing container might not be completely emptied. Thus, a
container which collapses in an uncontrolled manner may sometimes
trap some of the material and prevent its removal. Depletion
devices are commonly introduced into the containers so as to ensure
that the collapse of the container is controlled and all of the
material may be emptied.
[0025] The present invention can avoid the requirement for separate
depletion devices. By arranging for the collapse of some, but not
all, of the air chambers (and in particular not all of the air
chambers in the walls of the container), the container can
partially collapse as its contents are emptied, but can retain
enough structural rigidity to reduce or avoid the likelihood of
some of the material becoming trapped.
[0026] Two separate air networks can be provided, both of which
networks can be inflated to provide the container with structural
support during transportation. When the container has been
connected to the machine for emptying its contents, the first air
network can be opened or released to allow the container to
collapse as the contents are emptied, but the second air network
can be maintained so as to provide sufficient structural rigidity
to ensure complete emptying. In one embodiment, the air chambers
defining one side wall of the container are connected together as
the second air network, and the remaining air chambers are
connected together as the first air network.
[0027] In some embodiments of the various aspects of the present
invention therefore, all of the air chambers are interconnected in
a single air network. There is therefore only the need to undertake
one inflation operation for all of the air chambers. In other
embodiments the air chambers are arranged in two (or more) separate
air networks which must be inflated (and deflated) separately.
[0028] According to a third aspect of the invention, there is
provided a self-supporting container having at least one wall, a
base and a top, the wall being made of plastics material and
including at least one air chamber, the container having a spout
assembly with a first passageway adapted to permit material to be
introduced into and removed from the container and a valve to
permit the inflation of the at least one air chamber.
[0029] Preferably, the valve includes disabling means adapted to
open the valve. The disabling means can be operated to allow air to
flow out of the air chamber(s) when the container has been
emptied.
[0030] According to a fourth aspect of the invention, there is
provided a self-supporting container having at least one wall, a
base and a top, the top having a closable spout, the wall being
made of plastics material and including at least one air chamber,
the top being made of a two-layer material, the spout having a
passageway to permit a material to be introduced into and removed
from the container and a base plate surrounding the passageway, the
base plate being located between parts of each layer of material in
the top of the container.
[0031] In one method of manufacturing a container according to the
fourth aspect, the spout is fixed to one layer of wall material
before the second layer of wall material. Specifically, a first
layer of wall material is provided, and an opening in made through
the layer (which will provide the filling opening). A substantially
rigid spout is fixed by way of its base plate to the first layer,
with the passageway of the spout aligned with the opening. A second
layer of wall material is then laid over the first layer of wall
material, the second layer of wall material having a corresponding
opening to surround the passageway. The second layer of material is
fixed to the base plate of the spout whereby the spout is secured
between the two layers. In embodiments in which the spout is part
of a spout assembly which also provides the inflation valve, the
base plate can include a passageway communicating with the air
chamber(s) whereby air can be introduced between the layers of wall
material.
[0032] Ideally, the wall(s), base and top of the container are made
from a polyolefin such as polyethylene of polypropylene, or from
polyester, all of which are known to be suitable as packaging
materials. The spout or spout assembly can also be made from the
same material, whereby the container is made from a single material
and is ideally suited to recycling.
[0033] It will be understood that for some contained materials such
as milk, for which the shelf life is relatively short, the
migration of oxygen through the plastics walls of the container
will be so slow that the shelf life is unaffected. Some containers
will therefore not require an additional (usually metallic) layer
to reduce or prevent the passage of oxygen. With materials which
have a longer shelf-life, such as fruit juices for example, a
metallised layer to reduce or prevent the passage of oxygen may be
required, and whilst this will reduce the recyclability of the
empty container, it will not avoid its weight-saving advantages
over the known containers.
[0034] As above indicated, the wall(s) of the container are ideally
made from a two-ply sheet of plastics material. The regions of the
sheet which will form the respective air chambers are separated
from the regions of the sheet which will not form air chambers by
seams which join the two layers together.
[0035] The present invention therefore also provides a blank for
the container, the blank comprising two layers of plastics material
formed with seams joining selected parts of the layers together.
The blank can be folded and respective parts of the folded blank
joined together whereby to make a (collapsed or flattened)
container suitable for transportation to the user. The user can
simply pump air into the air chamber(s) whereby to erect the
container prior to (or preferably at the same time as) filling with
material.
[0036] Preferably, the seams are formed by a welding operation, so
that the use of other materials such as adhesives is avoided. This
facilitates recycling of the container since it can comprise a
single material.
[0037] When the container has been emptied by the customer, it can
be deflated (e.g. punctured), whereupon it will lose its structural
strength and can be collapsed so as to minimise the volume for
subsequent transportation. Preferably, the container can include a
weakened zone such as a tear strip or the like to facilitate
deflation when empty.
[0038] The fact that air is compressible adds a further advantage
to the present invention, in that the container can be squeezed and
will return to its erect shape when released. This is advantageous
for gelatinous products such as soups and the like, allowing their
easier removal from the container.
[0039] The fact that a layer of air surrounds part of the product
can also have an insulating effect, which can be beneficial during
transportation of a chilled product from the retailer to the
customer's home, for example. Again, the use of separate air
networks can be utilised, the first network comprising the
interconnected air chambers which provide the structural support
for the container, the second network comprising the wall(s) which
are inflated to provide insulation. The use of separate air
networks is desired since the pressure within the second
(insulation) network should typically be lower than the pressure
within the first (structural support) network.
[0040] According to a fifth aspect of the present invention there
is provided a collapsible container having four walls, a base and a
top, the base and the top being substantially rectangular, the top
having a closable spout, at least one air chamber defining each
corner of the container between adjacent walls, the walls, base and
top being of two-layer material, the collapsible container having
fold lines whereby to define the form of the container when
collapsed, there being at least one fold line in an opposing pair
of walls whereby the opposing walls are folded inwardly in the
collapsed container.
[0041] A collapsible container which can be folded in such a
fashion is often called a "gusseted bag" (or is often said to
utilise "side gussets"), and is known to be used with containers.
The layers of material forming the base and top are secured
together (as by welding) to define the required shape of the
container, and further fold lines can be provided for the base and
top, whereby parts of the base and top can be folded inwardly or
outwardly in order to provide a substantially flat bag ready for
erection and subsequent filling with material. Gusseted bags can
readily be erected into a container having a substantially flat
base and substantially flat sides. The present inventors are
apparently the first to utilise the benefits of a gusseted bag
arrangement for an inflatable container, and in particular for a
container having walls, top and base made of two-layer (or two-ply)
material.
[0042] The top of the collapsed container can be readily accessible
so that the filling spout and the inflation valve can be accessed
and the container can readily be erected (by inflation) at the same
time as it is filled.
[0043] Embodiments of the invention can use one or more of the
above aspects, as desired.
[0044] Whilst reference is made herein to "air chambers", it will
be understood that the chamber(s) can be filled with a gas other
than air if desired.
BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] The invention will now be described in more detail, by way
of example, with reference to the accompanying drawings, in
which:
[0046] FIG. 1 shows a blank for the container according to the
present invention;
[0047] FIG. 2 shows a perspective view from above of an erected
container according to the present invention;
[0048] FIG. 3 shows a perspective view from below of the container
of FIG. 2;
[0049] FIG. 4 shows a more detailed view of the top of the
container;
[0050] FIG. 5. shows a sectional view of part of the top of the
container;
[0051] FIG. 6 shows a side view of the spout assembly of the
container;
[0052] FIG. 7 shows a perspective view from below of the spout
assembly of FIG. 6;
[0053] FIG. 8 shows a perspective view from above of the spout
assembly of FIG. 6;
[0054] FIG. 9 shows a sectional view through the spout assembly of
FIG. 6;
[0055] FIG. 10 shows a sectional view of the valve member of the
spout assembly;
[0056] FIG. 11 shows a sectional view of an alternative spout
assembly;
[0057] FIG. 12 shows a perspective view from below of part of an
alternative embodiment of container according to the present
invention;
[0058] FIG. 13 shows a sectional view of part of the base of the
container of FIG. 12;
[0059] FIG. 14 shows a blank for an alternative container according
to the present invention;
[0060] FIG. 15 shows a perspective view from below of part of a
container produced from the blank of FIG. 14;
[0061] FIG. 16 shows a sectional view of the container of FIG.
15;
[0062] FIG. 17 shows a collapsed container according to the present
invention; and
[0063] FIG. 18 shows a blank for another alternative container
according to the invention.
DETAILED DESCRIPTION
[0064] The container 10 shown in FIG. 2 is constructed from a blank
12 shown in FIG. 1. The blank 12 comprises a two-ply polypropylene
sheet, i.e. sheet comprising two layers of polypropylene, one of
the layers overlying the other. The two layers are joined together
by a number of seams 14a-i, the seams being created by a welding
process or the like which is known to adhere two layers of
polypropylene together. In other embodiments the blank comprises a
two-ply sheet of another polyolefin material, such as
polyethylene.
[0065] The structure of the erected container shown in FIG. 2 is
dependent upon the arrangement of the seams 14, as will be
explained below. Whilst many of the seams 14 are interconnected,
they will be described separately below according to their
function.
[0066] The seam 14a defines the outer wall of an annular valve
chamber 16, and the seam 14b defines the inner wall of the annular
valve chamber. The seams 14c define the walls of a passage 20
connecting the valve chamber 16 to a top chamber 22.
[0067] The top chamber 22 is defined by a top seam 14d and a lower
seam 14e, and by respective parts of two side seams 14f.
[0068] The top seam 14d is continuous, as are the side seams 14f.
The side seams 14f are connected to a bottom seam 14g which is also
continuous.
[0069] The lower seam 14e is not continuous, and has a number of
gaps 24. Each of the gaps 24 is provided to permit air to pass from
the top chamber 22 into a respective wall air chamber 26. The sides
of each air chamber 26 are defined by longitudinal seams 14h, the
top of each air chamber is defined by a part of the lower seam 14e,
and the bottom of each air chamber 26 is defined by a part of the
upper seam 14i of the bottom chamber 30.
[0070] The bottom chamber 30 is defined by the upper seam 14i, the
bottom seam 14g, and respective parts of the side seams 14f. The
upper seam 14i has gaps 32 corresponding to the gaps 24 in the
lower seam 14e.
[0071] It will therefore be understood that when air is introduced
into the annular valve chamber 16 the air can pass through the
passage 20 and into the top chamber 22, through each of the gaps 24
into the respective air chambers 26, and through the gaps 32 into
the bottom chamber 30. The top chamber 22, the air chambers 26 and
the bottom chamber 30, can therefore all be filled with air, to the
pressure required, in one step.
[0072] The longitudinal seams 14h separate the air chambers 26 from
first regions 34 and second regions 36 which do not become filled
with air.
[0073] It will be understood that the blank 12 can be made from two
continuous layers of polypropylene material, i.e. the seams 14a-i
can be welded and the layers cut to form the blank 12, in a
substantially continuous operation.
[0074] In order to create the container 10, the blank 12 is folded
and the side edge 40 is welded or otherwise secured onto the side
edge 42. The top panel 44 and the bottom panel 46 are also folded
and welded or otherwise secured to form the top 50 of the container
and the base 52 of the container respectively.
[0075] It will be understood that as the top panel 44 is folded,
and the bottom panel 46 is folded, the top 50 and base 52 of the
container will have multiple sheets of polypropylene. In some
embodiments the salvage (i.e. the excess parts of the top panel 44
and bottom panel 46) is removed prior to being secured together, so
that the top wall 50 and the base 52 comprise substantially a
single (two-ply) sheet, so that the weight of the container 10 is
minimised.
[0076] In order to avoid outwardly-directed welded joints which
might make the container 10 less stable in use, at least the base
52 can be welded from the inside, if desired.
[0077] It will be understood that in the erected container shown in
FIGS. 2 and 3 two air chambers 26 define each of the vertical
corners of the container. The (narrower) first regions 34 are bent
to provide the corners of the container, whereas the (wider) second
regions 36 are substantially flat and provide much of the side
walls of the container.
[0078] A spout assembly or gland 54 is mounted to the top 50 of the
container 10. In this embodiment the spout assembly 54 is made of
polypropylene to match the material of the blank 12, and thereby
facilitate recycling of a used container. The spout assembly 54 is,
however, of considerably thicker material than the sheet making up
the blank 12, so that it is substantially rigid.
[0079] The spout assembly 54 is shown in more detail in FIGS. 4-10,
and comprises a base plate 56 which can be welded or otherwise
secured to the material at the top 50 of the container. Ideally,
the base plate 56 is secured between the two layers of
polypropylene which lie within the seam 14b defining the inner edge
of the annular valve chamber 16, whereby the annular valve chamber
16 surrounds the fill passageway 60 and the valve passageway
62.
[0080] Though not shown in FIG. 1, the blank 12 includes further
seams defining a passage 58 (see FIG. 5) whereby the valve
passageway 62 can communicate with the annular valve chamber 16. If
desired, in other embodiments the valve passageway 62 can overlie
the enlarged part 28 of the annular valve chamber 16 (see FIG. 1)
whereby air can pass directly into the valve chamber.
[0081] The base plate 56 carries a fill tube 64 which defines the
fill passageway 60, and has a screw thread 66 whereby to accept a
screw cap 70, in known fashion. The base plate 56 also carries a
valve tube 72 which defines the valve passageway 62. The valve tube
72 locates a valve member 74 as described in more detail below.
[0082] It will be understood that during the process of
manufacturing the container 10, a section of the polypropylene
material lying within the inner seam 14b is removed, and the border
of the removed material is welded or otherwise secured to the base
plate 56 surrounding the fill passageway 60, so that the fill
passageway 60 opens into the interior of the erected container.
[0083] Whilst it would be possible to fill the container 12 with
the chosen material by way of the base 52 (with the base panel 46
being closed and secured after filling), in the present embodiment
it is desired that the container 10 is filled by way of the spout
assembly 54, and specifically by way of the fill tube 64. Ideally,
the filling machine includes means to hold the fill tube 64 during
filling of the container, and also includes means to pump air into
the valve tube 72. Accordingly, a filling machine can pump air into
the air chambers 22, 26 and 30 of the container 10 whereby to erect
the container, at substantially the same time as the container is
being filled with product.
[0084] The added complexity of the means to pump air into the valve
tube 72 is relatively minor compared to a machine required to erect
a carton board container, and is not likely to be a barrier to
users. In addition, it is likely to take far less time to fill the
air chambers 22, 26, 30 with air than it is to fill the container
12 with liquid, so that the inflation step will not impact
adversely upon the filling process.
[0085] The valve member 74 is located in the "open" position shown
in FIGS. 5, 6 and 9 as air is being pumped into the air chambers
22, 26, 30, air being able to pass through the openings 78 in the
valve member 74. When the required air pressure within the air
chambers 22, 26, 30 has been reached, the valve member is pressed
into the valve tube 72, to the "closed" position shown in FIG. 10,
sealing the air within the air chambers 22, 26, 30 and maintaining
the self-supporting structural rigidity of the container 10.
[0086] FIG. 11 shows an alternative embodiment of spout assembly
154 (without the screw cap) in which the fill tube 164 is
manufactured as a separate component to the base plate 156. These
components are secured together by complementary formations 80. The
advantage of such an arrangement is that the screw cap does not
need to be screwed onto the fill tube 164 after the container has
been filled, this being a relatively slow operation. Instead, the
fill tube 164 and its pre-fitted screw cap can be pressed into
position after the container has been filled.
[0087] FIGS. 12 and 13 show the bottom part of an alternative
container 110, made from an alternative design of blank. The top
part of the container 110 is not shown, but may be similar to the
top part of the container 10 for example. In the container 110 the
base 152 has base air chambers 82 in addition to the bottom chamber
130. The base air chambers 82 are connected to the bottom chamber
130 by respective gaps in the bottom seam of the blank. The base
air chambers 82 provide a more rigid base, and help to define the
structure of the container 110 when the air chambers are filled. In
a particularly preferred embodiment, the salvage of the bottom
panel of the blank is welded after the air chambers 22, 26, 130 and
82 have been filled which will secure the base in its erected
condition.
[0088] It will be understood that the top 50 of the container 10
can be gabled or substantially flat, or made as a single continuous
panel, as desired, depending upon the form of the blank and the
folding and welding steps.
[0089] An alternative design of blank 212 for producing a container
is shown in FIG. 14, and the bottom of a container 210 which is
produced from the blank is shown in FIGS. 15 and 16. The container
210 which is produced from the blank 212 has several similarities
with the container 10, namely four walls (which are substantially
vertical in use), a top including a spout assembly, and a base.
[0090] The blank 212 differs from the blank 12 in providing only a
single air chamber 226 for each of the (vertical) corners of the
container. Thus, in this embodiment the annular valve chamber 216
is connected to the top chamber 220, which in turn is connected to
the bottom chamber 230 by way of only four air chambers 226.
[0091] The blank 212 also differs from the blank 12 in having base
air chambers which will provide the structure of the base 252
(somewhat similar to the blank used to form the container 110 of
FIGS. 12 and 13). Specifically, the bottom chamber 230 is connected
to two primary base air chambers 84 and two secondary base air
chambers 86. As shown in FIG. 15, in the erected container 210 (in
which the edges 240 and 242 have been secured together) the
respective primary base air chambers 84 lie on opposed sides of the
base 252, and the respective secondary base air chambers 86 lie on
opposed sides of the base, between the primary base air chambers
84.
[0092] Importantly, the dimension d of the primary base air
chambers 84 is slightly greater than half of the dimension w which
is the width of the base 252 (inside the bottom chamber 230) of the
erected container. When the edges 88 of the primary base air
chambers 84 are secured together the combined dimension 2d of the
primary base air chambers exceeds the width w of the erected
container. When the primary base air chambers 84 are filled with
air they are not able to lie in a common plane, i.e. the base 252
is not flat, but instead the primary base air chambers 84 tend to
push the base inwards (concave) or outwards (convex). It can be
arranged that the machine which fills the air chambers (and which
is ideally the machine which also fills the container with
product), will drive (and hold) the base in its concave
position.
[0093] The secondary base air chambers 86 act to lock the primary
base air chambers 84 in position, i.e. they enhance the
"over-centre" arrangement. It is arranged in particular that the
force with which the primary and second base air chambers 84,86
tend to maintain the concave position will exceed the weight of the
contents which seeks to push the base 252 towards its convex
position.
[0094] It will be noted that the annular valve chamber 216 is
larger than the annular valve chamber 16 relative to the width w of
the base (and top). The blank 212 therefore provides a container
with a relatively larger spout assembly. It could be arranged in an
alternative embodiment that the spout assembly spans substantially
all of the top of the container, which is desirable when the
contained product is a solid which does not readily flow, for
example breakfast cereals such as corn flakes.
[0095] The blank 212 also differs from the blank 12 in providing
notches 90 in the bottom chamber 230. When the container is erected
from the blank 212 the notches 90 lie at the respective outer
corners of the base 252. The reduction in the cross-section of the
bottom chamber 230 at each corner serves to "flatten" the base,
i.e. it removes excess material which might otherwise fold or
buckle at the corners.
[0096] As shown in FIGS. 15 and 16, the erected container 210 will
rest upon the bottom chamber 230, the bottom chamber 230 providing
the junction between the walls and base of the erected container.
The container therefore rests upon the periphery of its base rather
than the whole of its base (similar to a wine bottle). It will be
much easier to ensure that the periphery of the base is
substantially flat than the whole of the base, with the result that
the erected container 210 is more stable. In addition, since the
contact area upon which the erected container 210 rests is
relatively small, less care needs to be taken over the seams of the
base 252, as only those seams which lie within the contact area
affect the stability of the container.
[0097] Another alternative blank 312 for producing a container is
shown in FIG. 17. The blank 312 differs from the blanks 12 and 212
in having two separate air networks. The air networks are both
designed to be filled by way of the spout assembly (not shown), and
so the blank 312 has two separate valve air chambers 316a, 316b,
each having its own enlarged part 328a and 328b which can be
connected to a respective valve tube. The spout assembly therefore
has two separate valve openings, perhaps similar to the valve
openings 62 (and two separate valves), one for each of the air
networks.
[0098] The valve chamber 316a communicates with the top chamber 322
and wall air chambers 326 in a similar fashion to the blanks 12 and
212. The air chambers 326 communicate with the bottom chamber 330
(and hence to the base air chambers 384 and 386) by way of a single
gap 332 in the upper seam 314i.
[0099] An additional seam 314h is provided between the upper seam
314i and the air chambers 326, and an additional seam 314j is
provided inside the seam 314f. The chambers formed between the
seams 314f and 314j, and between the seams 314i and 314h, comprise
conduits of a second air network. The seam 314h has openings 92
therethrough, each of the openings 92 communicating with a
respective wall panel 336. Air can therefore be delivered through
the valve chamber 316b into the second air network which includes
the wall panels 336.
[0100] The blank 312 is suitable for producing an insulating
container, with the first air network being filled with
higher-pressure air so as to provide the structure of the
container, and the second air network being filled with lower
pressure air so as to provide an insulating layer for the wall
panels.
[0101] It will be understood that the configuration of the first
air network and the second air network can be varied by varying the
configuration of the seams on the blank. In one alternative
embodiment the first air network is filled with air to inflate
three of the four walls of the container and perhaps also the base,
whilst the second air network is filled with air to inflate the
fourth wall. Such an embodiment would avoid the requirement for a
depletion device when used for a product which should not come into
contact with air, the first air network being deflated as the
container is emptied, the second air network being maintained so as
to avoid total collapse of the container and avoid the potential
trapping of some of the product.
[0102] The blank 312 also shows another feature, which serves to
form a collapsed container 310 of FIG. 18. After forming of the
blank 312, and prior to folding of the blank, fold lines 94 and 96
are formed therein. The fold lines 94 are formed to fold inwardly
(i.e. down into the paper as drawn, whereas the fold lines 96 are
formed to fold outwardly (i.e. up from the paper as drawn).
Following connection of the edges 340 and 342, and the folding and
welding of the top panel 344 and the bottom panel 346 to form the
top 350 and base 352 respectively of the container 310, the
container may be folded into the gusseted bag shown in FIG. 18
[0103] It will be understood that the blanks 12 and 212 can also be
modified to provide two separate air networks, and/or to provide a
gusseted bag, if desired. In fact, the features which are shown for
each blank 12, 212, 312 are generally interchangeable so as to
provide a blank having all of the desired features of the resulting
container.
[0104] A means for deflating the container is shown in FIG. 1. A
weakened section 38 of one or both of the layers of polypropylene
are provided at a chosen location of the container. In this
embodiment the weakened section 38 is provided in the top chamber
22, but it will be understood that it could be provided in
alternative locations such as the base or one of the walls, as
desired. A strip of material 48 is secured adjacent to the weakened
section 38, and in this embodiment lies between the two sheets of
polypropylene, so that a part of the strip 48 lies within the top
chamber 22, and a part lies outside the top chamber. When the
container has been erected a part of the outer layer of
polypropylene (within the top panel 44) is removed to expose the
end of the strip 48 and allow the tear strip to be gasped by the
user. When the container has been emptied and it is desired to
deflate the container the strip may be pulled to tear or rupture
the weakened section 38, and allow the escape of air.
[0105] It will be understood that a tear strip such as 48 and a
weakened section such as 38 can be used in the other embodiments
(and blanks) described herein. In containers having two air
networks, a single tear strip can span both of the air networks so
that they are deflated together, or separate tear strips can be
provided for each air network, whereby the separate air networks
can be deflated separately.
[0106] In other embodiments a strip of material similar to the
strip 48 is adhered to one of the layers of polypropylene adjacent
to the weakened section 38, i.e. the tear strip does not lie
between the two sheets of polypropylene. In yet other alternative
embodiments the tear strip is extended to project beyond the top
panel 44, so that it is not necessary to remove a part of the top
panel in order to expose the tear strip.
[0107] It will be understood that the container does not need to be
square in plan view, but could instead be oblong. Other shapes such
as triangular, hexagonal or cylindrical could be provided if
desired, but rectangular shapes are preferred because they minimise
the volume of wasted space during transportation.
[0108] Tests undertaken by the inventors have demonstrated that
whilst the air chambers add thickness to the walls of the
container, the detrimental effect upon the transportation
utilisation (when full) is minor. Thus, a one litre container (such
as the container 10) having a footprint identical to that of a one
litre carton board container would need to only a few millimetres
taller that the carton board container. This difference in height
is a small disadvantage compared to the weight, processing and
recycling advantages of the containers of the present invention.
The increase in height over a corresponding carton board container
would be less for larger-volume containers in which the footprint
is larger. A container according to the present invention is both
lighter and more space efficient than the known HDPE plastics
containers used for milk.
* * * * *