BLOW NOZZLE TO CONTROL LIQUID FLOW WITH
PRE-STRETCH ROD ASSEMBLY
CROSS-REFERENCE TO RELATED APPLICATIONS
5 [OOOI] This application claims priority to U.S. Utility Application No.
131267,974, filed on October 7, 201 1, and the benefit of U.S. Provisional
Application No. 611393,408, filed on October 15, 201 0. The entire disclosures of
the above applications are incorporated herein by reference.
Fl ELD
[0002] This disclosure generally relates to molds for filling containers
with a commodity, such as a liquid commodity. More specifically, this disclosure
relates to a blow nozzle to control liquid flow with pre-stretch rod assemblies
used for fillinglforming blown plastic containers.
15
BACKGROUND
[0003] This section provides background information related to the
present disclosure which is not necessarily prior art.
[0004] As a result of environmental and other concerns, plastic
20 containers, more specifically polyester and even more specifically polyethylene
terephthalate (PET) containers are now being used more than ever to package
numerous commodities previously supplied in glass containers. Manufacturers
and fillers, as well as consumers, have recognized that PET containers are
lightweight, inexpensive, recyclable and manufacturable in large quantities.
25 [0005] Blow-molded plastic containers have become commonplace in
packaging numerous commodities. PET is a crystallizable polymer, meaning
that it is available in an amorphous form or a semi-crystalline form. The ability of
a PET container to maintain its material integrity relates to the percentage of the
PET container in crystalline form, also known as the "crystallinity" of the PET
30 container. The following equation defines the percentage of crystallinity as a
volume fraction:
% Crystallinity = ( -Pa )r100
Pc -Pa
where p is the density of the PET material; pa is the density of pure amorphous
PET material (1.333 glcc); and p, is the density of pure crystalline material
(1.455 glcc).
5 [0006] Container manufacturers use mechanical processing and
thermal processing to increase the PET polymer crystallinity of a container.
Mechanical processing involves orienting the amorphous material to achieve
strain hardening. This processing commonly involves stretching an injection
molded PET preform along a longitudinal axis and expanding the PET preform
10 along a transverse or radial axis to form a PET container. The combination
promotes what manufacturers define as biaxial orientation of the molecular
structure in the container. Manufacturers of PET containers currently use
mechanical processing to produce PET containers having approximately 20%
crystallinity in the container's sidewall.
15 [0007] Thermal processing involves heating the material (either
amorphous or semi-crystalline) to promote crystal growth. On amorphous
material, thermal processing of PET material results in a spherulitic morphology
that interferes with the transmission of light. In other words, the resulting
crystalline material is opaque, and thus, generally undesirable. Used after
20 mechanical processing, however, thermal processing results in higher
crystallinity and excellent clarity for those portions of the container having biaxial
molecular orientation. The thermal processing of an oriented PET container,
which is known as heat setting, typically includes blow molding a PET preform
against a mold heated to a temperature of approximately 250°F - 350°F
25 (approximately 121 "C - 177"C), and holding the blown container against the
heated mold for approximately two (2) to five (5) seconds. Manufacturers of PET
juice bottles, which must be hot-filled at approximately 185°F (85"C), currently
use heat setting to produce PET bottles having an overall crystallinity in the
range of approximately 25% -35%.
[0008] Conventionally, blowing forming containers has always been
accomplished using high-pressure air blowing into a softened plastic form, such
as an injection molded preform or an extruded parison tube. Typically, a blow
nozzle is introduced into the neck of the container and air pressure forms the
5 container by blowing the softened plastic out to a mold. Separately, liquid filling
nozzles, though designed to fill pre-blown containers, do not incorporate a
stretching rod.
SUMMARY
10 [0009] This section provides a general summary of the disclosure, and
is not a comprehensive disclosure of its full scope or all of its features.
[OOIO] According to the principles of the present disclosure, an
apparatus for forming a container using a rod and pressurized fluid is provided.
The apparatus comprises a housing and a rod apparatus disposed in the housing.
15 The rod apparatus includes a rod for at least partially forming a container
preform. The apparatus further includes a nozzle system disposed in the
housing that is operably coupled with the rod apparatus. The nozzle system is
positionable between a first position preventing pressurized fluid from being
injected into the container preform and a second position permitting pressurized
20 fluid to be injected into the container preform.
[OOII] Further areas of applicability will become apparent from the
description provided herein. The description and specific examples in this
summary are intended for purposes of illustration only and are not intended to
limit the scope of the present disclosure.
DRAWINGS
[0012] The drawings described herein are for illustrative purposes only
of selected embodiments and not all possible implementations, and are not
intended to limit the scope of the present disclosure.
30 [0013] FIG. 1 is a partial, lower cross-sectional view illustrating an
apparatus for forming a container using an optional stretch rod and pressurized
liquid, wherein the portion left of the centerline illustrates an extended position
and the portion right of the centerline illustrates a retracted position; and
[0014] FIG. 2 is a partial, upper cross-sectional view illustrating the
apparatus of FIG. 1 for forming a container using an optional stretch rod and
5 pressurized liquid wherein the portion left of the centerline illustrates an
extended position and the portion right of the centerline illustrates a retracted
position.
[0015] Corresponding reference numerals indicate corresponding parts
throughout the several views of the drawings.
DETAILED DESCRIPTION
[0016] Example embodiments will now be described more fully with
reference to the accompanying drawings. Example embodiments are provided
so that this disclosure will be thorough, and will fully convey the scope to those
15 who are skilled in the art. Numerous specific details are set forth such as
examples of specific components, devices, and methods, to provide a thorough
understanding of embodiments of the present disclosure. It will be apparent to
those skilled in the art that specific details need not be employed, that example
embodiments may be embodied in many different forms and that neither should
20 be construed to limit the scope of the disclosure.
[0017] The terminology used herein is for the purpose of describing
particular example embodiments only and is not intended to be limiting. As used
herein, the singular forms "a", "an" and "the" may be intended to include the
plural forms as well, unless the context clearly indicates otherwise. The terms
25 "comprises," "comprising," "including," and "having," are inclusive and therefore
specify the presence of stated features, integers, steps, operations, elements,
and/or components, but do not preclude the presence or addition of one or more
other features, integers, steps, operations, elements, components, and/or groups
thereof. The method steps, processes, and operations described herein are not
30 to be construed as necessarily requiring their performance in the particular order
discussed or illustrated, unless specifically identified as an order of performance.
It is also to be understood that additional or alternative steps may be employed.
[0018] When an element or layer is referred to as being "on", "engaged
to", "connected to" or "coupled to" another element or layer, it may be directly on,
engaged, connected or coupled to the other element or layer, or intervening
elements or layers may be present. In contrast, when an element is referred to
5 as being "directly on," "directly engaged to", "directly connected to" or "directly
coupled to" another element or layer, there may be no intervening elements or
layers present. Other words used to describe the relationship between elements
should be interpreted in a like fashion (e.g., "between" versus "directly between,"
"adjacent" versus "directly adjacent," etc.). As used herein, the term "and/or"
10 includes any and all combinations of one or more of the associated listed items.
[0019] Although the terms first, second, third, etc. may be used herein
to describe various elements, components, regions, layers and/or sections,
these elements, components, regions, layers and/or sections should not be
limited by these terms. These terms may be only used to distinguish one
15 element, component, region, layer or section from another region, layer or
section. Terms such as "first," "second," and other numerical terms when used
herein do not imply a sequence or order unless clearly indicated by the context.
Thus, a first element, component, region, layer or section discussed below could
be termed a second element, component, region, layer or section without
20 departing from the teachings of the example embodiments.
[0020] Spatially relative terms, such as "inner," "outer," "beneath",
"below", "lower", "above", "upper" and the like, may be used herein for ease of
description to describe one element or feature's relationship to another
element(s) or feature(s) as illustrated in the figures. Spatially relative terms may
25 be intended to encompass different orientations of the device in use or operation
in addition to the orientation depicted in the figures. For example, if the device in
the figures is turned over, elements described as "below" or "beneath" other
elements or features would then be oriented "above" the other elements or
features. Thus, the example term "below" can encompass both an orientation of
30 above and below. The device may be otherwise oriented (rotated 90 degrees or
at other orientations) and the spatially relative descriptors used herein
interpreted accordingly.
[0021] The present teachings provide for a blow mold device and
nozzle system, and method of using the same, to permit the use of liquids as an
injecting agent during the forming process. These liquids can be a disposable
liquid or, in some embodiments, can comprise the liquid commodity. Therefore,
5 in some embodiments, the liquids used for forming the container can remain
therein for final packaging. The blow mold device and nozzle system provides
controlled use of the liquid to minimize chances of contamination and prevent
leakage during cycling. According to these principles, formation and filling of a
container can be achieved in a single step without sacrificing clean and sanitary
10 conditions.
[0022] As will be discussed in greater detail herein, the shape of the
mold device and nozzle system of the present teachings and the container
formed therewith can be formed according to any one of a number of variations.
By way of non-limiting example, the mold of the present disclosure can be
15 configured to hold any one of a plurality of containers and be used in connection
with a number of fluids and commodities, such as beverages, food, or other hotfill
type materials.
[0023] It should be appreciated that the size and the exact shape of
the mold device and nozzle system are dependent on the size of the container
20 and the required operational parameters. Therefore, it should be recognized that
variations can exist in the presently described designs. According to some
embodiments, it should also be recognized that the mold can comprise various
features for use with containers having vacuum absorbing features or regions,
such as panels, ribs, slots, depressions, and the like.
[0024] The present teachings relate to the forming of one-piece plastic
containers using a liquid. Generally, these containers, after formation, generally
define a body that includes an upper portion having a cylindrical sidewall forming
a finish. Integrally formed with the finish and extending downward therefrom is a
shoulder portion. The shoulder portion merges into and provides a transition
30 between the finish and a sidewall portion. The sidewall portion extends
downward from the shoulder portion to a base portion having a base. An upper
transition portion, in some embodiments, may be defined at a transition between
the shoulder portion and the sidewall portion. A lower transition portion, in some
embodiments, may be defined at a transition between the base portion and the
sidewall portion.
[0025] The exemplary container may also have a neck. The neck may
5 have an extremely short height, that is, becoming a short extension from the
finish, or an elongated height, extending between the finish and the shoulder
portion. The upper portion can define an opening. Although the container is
shown as a drinking container and a food container, it should be appreciated that
containers having different shapes, such as sidewalls and openings, can be
10 made according to the principles of the present teachings.
[0026] The finish of the plastic container may include a threaded
region having threads, a lower sealing ridge, and a support ring. The threaded
region provides a means for attachment of a similarly threaded closure or cap
(not illustrated). Alternatives may include other suitable devices that engage the
15 finish of the plastic container, such as a press-fit or snap-fit cap for example.
Accordingly, the closure or cap (not illustrated) engages the finish to preferably
provide a hermetical seal of the plastic container. The closure or cap (not
illustrated) is preferably of a plastic or metal material conventional to the closure
industry and suitable for subsequent thermal processing.
20 [0027] The container can be formed according to the principles of the
present teachings. A preform version of the container includes a support ring,
which may be used to carry or orient the preform through and at various stages
of manufacture. For example, the preform may be carried by the support ring,
the support ring may be used to aid in positioning the preform in a mold cavity, or
25 the support ring may be used to carry an intermediate container once molded.
At the outset, the preform may be placed into the mold cavity such that the
support ring is captured at an upper end of the mold cavity. In general, the mold
cavity has an interior surface corresponding to a desired outer profile of the
blown container. More specifically, the mold cavity according to the present
30 teachings defines a body forming region, an optional moil forming region and an
optional opening forming region. Once the resultant structure, hereinafter
referred to as an intermediate container, has been formed, any moil created by
the moil forming region may be severed and discarded. It should be appreciated
that the use of a moil forming region and/or opening forming region are not
necessarily in all forming methods.
[0028] In one example, a machine places the preform 100 (see FIG. 1)
5 heated to a temperature between approximately 1 90 OF to 250 OF (approximately
88°C to 121 OC) into the mold cavity. The mold cavity may be heated to a
temperature between approximately 250 OF to 350 OF (approximately 1 21 OC to
177°C). An internal stretch rod apparatus 20 (see FIGS. 1 and 2) stretches or
extends the heated preform within the mold cavity thereby molecularly orienting
10 the polyester material in an axial direction generally corresponding with the
central longitudinal axis of the container. While the stretch rod extends the
preform, a liquid assists in extending the preform in the axial direction and in
expanding the preform in a circumferential or hoop direction thereby substantially
conforming the polyester material to the shape of the mold cavity and further
15 molecularly orienting the polyester material in a direction generally perpendicular
to the axial direction, thus establishing the biaxial molecular orientation of the
polyester material in some, most, or all of the intermediate container. In some
embodiments, the pressurized liquid holds the mostly biaxial molecularly
oriented polyester material against the mold cavity for a period of time before
20 removal of the intermediate container from the mold cavity.
[0029] With particular reference to FIGS. 1 and 2, a mold device and
nozzle system 10 is provided comprising internal stretch rod apparatus 20 and a
nozzle system 22 formed therewith that are each independently actuatable and
yet, in some embodiments, actuatable simultaneously. Internal stretch rod
25 apparatus 20 comprises a stretch rod member assembly 24 being slidably
disposed within a housing 26. The internal stretch rod member assembly 24 and
nozzle system 22 are illustrated in both an extended and retracted positions (left
of centerline CL in FIGS. 1 and 2 and right of centerline CL in FIGS. 1 and 2,
respectively). Stretch rod member assembly 24 can comprise a stretch rod 28
30 being slidably disposed (at least indirectly) within a central bore 30 of housing
26. Stretch rod 28 is generally cylindrical in shape having an engaging tip
portion 32 at a distal end and a piston portion 34 at a proximal end. Tip portion
32 is shaped to engage preform 100 during manufacture, shaping, and/or filling.
Piston portion 34 is received within a piston chamber 36 to closely conform
therewith to define a piston assembly (for example pneumatic, hydraulic, servo,
mechanical or the like). Piston portion 34 is responsive to changes in
5 pneumatic, hydraulic, servo, mechanical or the like pressure within piston
chambers 36A and 36B, thereby causing piston portion 34 to move in a direction
generally aligned with centerline CL between an extended position (left side) and
a retracted position (right side). Movement of piston portion 34 thereby causes
associated movement of stretch rod 28 and tip portion 32.
10 [0030] Additionally, in some embodiments, nozzle system 22
comprises a seal rod 50 being slidably disposed within housing 26. That is,
nozzle system 22 can comprise a seal rod 50 being slidably disposed within
central bore 30 of housing 26. Seal rod 50 includes an engaging seal portion 52
at a distal end and a piston portion 66 at a proximal end. Seal portion 52 is
15 shaped to engage a narrowed distal portion 56 of central bore 30. In this way,
seal portion 52 can be position in a retracted position where seal portion 52 is
spaced apart from an enlarged intermediate portion 31 of central bore 30 to
permit the flow of liquid there past. Seal portion 52 can also be positioned in an
extended and seated position where seal portion 52 sealingly engages narrowed
20 distal portion 56. In the extended and seated position, seal portion 52 permits
liquid to flow from a fluid inlet 58, through an annulus 60 of central bore 30 to
enlarged intermediated portion 31 of central bore 30. However, in this position,
flow out of nozzle system 22 is prohibited. In the retracted position, seal portion
52 is spaced apart from narrowed distal portion 56 and thus permits liquid to flow
25 from fluid inlet 58, through annulus 60 of central bore 30 to enlarged
intermediated portion 31 of central bore 30 and out fluid injector 62 and into
preform 100. The fluid pressure within preform 100 causes preform 100 to
expand and be molded into a predetermined shape conforming to the mold
cavity. To achieve a desired final shape, fluid pressure typically needs to be
30 selected that is sufficiently high to urge the preform into all portions of the mold
cavity. Upon completion of the molding process, seal portion 52 can return to
the extended and seated position to thereby seal fluid injector 62 and prevent
further flow of the liquid from the nozzle.
[0031] Seal portion 52 is moved in response to movement of piston
portion 66. Piston portion 66 of nozzle system 22 is received within a piston
5 chamber 68 to closely conform therewith to define a piston assembly. Piston
portion 66 is responsive to changes in pressure from inlet 67 within piston
chambers 68A and 68B, thereby causing piston portion 66 to move in a direction
generally aligned with centerline CL between the extended and seated position
(left side) and the retracted position (right side). Movement of piston portion 66
10 thereby causes associated movement of seal rod 50 and seal portion 52. It
should be appreciated, however, that although pressurized liquid has been
discussed in connection with the present teachings, in some embodiments,
pressurized air or a combination of pressurized air and liquid can be used.
Moreover, it should be appreciated that the pressurized liquid can be a forming
15 liquid used only for molding or could be a liquid commodity that is intended to
remain within the container upon completion.
[0032] With continued reference to FIGS. 1 and 2, in some
embodiments, stretch rod 28 of stretch rod assembly 24 can be slidably
disposed within seal rod 50 of nozzle system 22. That is, seal rod 50 can
20 comprise a central seal rod slot or bore 51 that extends axially along seal rod 50.
Seal rod slot 51 can be generally sized and shaped to permit slidably movement
relative to stretch rod 28 to permit independent and/or simultaneous actuation of
either or both stretch rod assembly 24 and nozzle system 22. In some
embodiments, seal rod slot 51 can be generally cylindrical and stretch rod 28
25 can likewise be generally cylindrical. In this way, stretch rod 28 and seal rod 50
can be coaxially aligned within central bore 30. Moreover, as discussed herein,
in some embodiments an annulus 60 can be formed external to seal rod 50
within central bore 30.
[0033] In some embodiments, as illustrated in FIG. 1, housing 26 can
30 comprise a ring depression 70 formed along a bottom side of housing 26 to
sealingly receive preform 100 along the threaded region, the lower sealing ridge,
and/or the support ring.
[0034] Alternately, other manufacturing methods using other
conventional materials including, for example, thermoplastic, high density
polyethylene, polypropylene, polyethylene naphthalate (PEN), a PETIPEN blend
or copolymer, and various multilayer structures may be suitable for the
5 manufacture of the plastic container. Those having ordinary skill in the art will
readily know and understand plastic container manufacturing method
alternatives.
[0035] The foregoing description of the embodiments has been
provided for purposes of illustration and description. It is not intended to be
10 exhaustive or to limit the invention. Individual elements or features of a
particular embodiment are generally not limited to that particular embodiment,
but, where applicable, are interchangeable and can be used in a selected
embodiment, even if not specifically shown or described. The same may also be
varied in many ways. Such variations are not to be regarded as a departure from
15 the invention, and all such modifications are intended to be included within the
scope of the invention.

CLAIMS
What is claimed is:
1. An apparatus for forming a container, said apparatus comprising:
a housing;
a rod apparatus disposed in said housing, said rod apparatus having a
rod for at least partially forming a container preform; and
a nozzle system disposed in said housing and operably coupled with said
rod apparatus, said nozzle system being actuatable between a first position
10 preventing pressurized fluid from being injected into the container preform and a
second position permitting pressurized fluid to be injected into the container
preform.
2. The apparatus according to Claim 1 wherein said rod is movable
15 between an extended position and a retracted position and controllable to
positions therebetween.
3. The apparatus according to Claim 2 wherein said rod is
independently actuatable relative to said nozzle system.
20
4. The apparatus according to Claim 2 wherein said rod is
independently and simultaneously actuatable relative to said nozzle system.
5. The apparatus according to Claim 1 wherein said housing includes
25 a central bore, said rod being slidably disposed within said central bore.
6. The apparatus according to Claim 5 wherein said nozzle system
includes a seal rod, said seal rod forming a seal interface when said nozzle
system is in said first position preventing pressurized fluid from being injected
30 into the container preform, said seal rod being disposed in said central bore of
said housing.
7. The apparatus according to Claim 5 wherein said seal rod
comprising a seal rod slot, said rod being slidably disposed within said seal rod
slot.
5 8. The apparatus according to Claim 7 wherein said rod and said seal
rod are coaxially aligned.
9. The apparatus according to Claim 1 wherein said nozzle system
comprises a seal rod being slidably disposed within said housing, said seal rod
10 having a seal portion on a distal end thereof.
10. The apparatus according to Claim 9 wherein said nozzle system
comprises a piston disposed on a proximal end of said seal rod for movement
therewith, said piston being movable in response to a force exerted thereon.
15
11. The apparatus according to Claim 1 wherein said rod apparatus
comprises a piston disposed on a proximal end of said rod for movement
therewith, said piston being movable in response to a force exerted thereon.
20 12. The apparatus according to Claim 11 wherein said rod includes a
tip portion disposed on a distal end thereof physically engagable with the
container preform.
13. The apparatus according to Claim 1 wherein said housing includes
25 a central bore and said nozzle system includes a seal rod being slidably
disposed within said central bore, said seal rod forming a seal interface when
said nozzle system is in said first position preventing pressurized fluid from being
injected into the container preform.
14. The apparatus according to Claim 1 wherein said nozzle system
comprises:
a central bore extending through said housing and said rod includes a tip
portion on a distal end thereof engagable with the container preform and a piston
member on a proximal end thereof, said rod being disposed in said central bore,
said piston member being actuatable in response to a pressure means to
5 actuate said rod between an extended position and a retracted position.
15. The apparatus according to Claim 1 wherein said nozzle system
comprises:
a central bore extending through said housing; and
10 a seal rod having a seal portion on a distal end thereof engagable with a
portion of the central bore and a piston member on a proximal end thereof, said
seal rod being disposed in said central bore, said piston member being
actuatable in response to a pressure means to actuate said seal rod between
said first position preventing said pressurized fluid from being injected into the
15 container preform and said second position permitting said pressurized fluid to
be injected into the container preform.
16. An apparatus for forming a container, said apparatus comprising:
a housing having a central bore;
20 a stretch rod apparatus disposed in said housing, said stretch rod
apparatus having a stretch rod extending through said central bore for at least
partially forming a container preform; and
a nozzle system disposed in said housing and operably coupled with said
stretch rod apparatus, said nozzle system having a seal rod extending through
25 said central bore being generally coaxial with said stretch rod, said nozzle
system being positionable between a first position preventing pressurized fluid
from being injected into the container preform and a second position permitting
pressurized fluid to be injected into the container preform.
17. The apparatus according to Claim 16 wherein said stretch rod is
movable between an extended position and a retracted position.
18. The apparatus according to Claim 17 wherein said stretch rod is
independently actuatable relative to said nozzle system.
19. The apparatus according to Claim 17 wherein said stretch rod is
5 independently and simultaneously actuatable relative to said nozzle system.
20. The apparatus according to Claim 16 wherein said stretch rod is
slidably disposed within said central bore.
10 21. The apparatus according to Claim 20 wherein said seal rod forming
a seal interface when said nozzle system is in said first position preventing
pressurized fluid from being injected into the container preform.
22. The apparatus according to Claim 20 wherein said seal rod
15 comprising a seal rod slot, said stretch rod being slidably disposed within said
seal rod slot of said seal rod.
23. The apparatus according to Claim 16 wherein said seal rod is
slidably disposed within said central bore of said housing, said seal rod having a
20 seal portion on a distal end thereof.
24. The apparatus according to Claim 23 wherein said nozzle system
comprises a piston disposed on a proximal end of said seal rod for movement
therewith, said piston being movable in response to a force exerted thereon.
25. The apparatus according to Claim 16 wherein said stretch rod
apparatus comprises a piston disposed on a proximal end of said stretch rod for
movement therewith, said piston being movable in response to a force exerted
thereon.
26. The apparatus according to Claim 25 wherein said stretch rod includes a tip portion disposed on a distal end thereof physical engagable with the container preform.
27. The appartus according to Claim 16 wherein said housing includes a central bore and said nozzle system includes seal rod being slidably disposed within said central bore, said seal rod forming a seal interface when said nozzle system is in said first position preventing pressurized fluid from being injected into the container preform.
28. The apparatus according to Claim 16 wherein said stretch rod includes a tip portion on a distal end thereof engagable with the container preform and a piston member on a proximal end thereof, said piston member being actuable in responce to a pressure means to actuate said stretch rod between an extended position and a retracted position.
29. The apparatus according to Claim 16 wherein said seal rod comprises a seal portion on a distal end thereof engagable with a portion of the central bore and a piston member on a proximal end thereof, said piston member being actuable in responce to a pressure means to actuate said seal rod between said first position preventing said pressurized fluid from being injected into the container preform and said secong position permitting said pressurized fluid to be injected into the container preform.