U.S. patent application number 15/863401 was filed with the patent office on 2018-07-12 for molding systems and related methods.
The applicant listed for this patent is Friendship Products LLC. Invention is credited to Timothy Carlson, B. Everett Hendrickson, Paul McCutcheon, Craig Severn.
Application Number | 20180194058 15/863401 |
Document ID | / |
Family ID | 62782217 |
Filed Date | 2018-07-12 |
United States Patent
Application |
20180194058 |
Kind Code |
A1 |
Hendrickson; B. Everett ; et
al. |
July 12, 2018 |
MOLDING SYSTEMS AND RELATED METHODS
Abstract
A system for molding an object includes an articulated mold
having an axis and a plurality of mold portions configured to
collectively define a molding cavity for shaping the object when
arranged in respective molding positions. The system includes a
plurality of actuators, each operatively coupled to a respective
mold portion and configured to move the respective mold portion
along the axis from the respective molding position toward a
respective ejecting position for releasing the object. The system
includes a controller in communication with each of the plurality
of actuators and configured to independently activate each of the
plurality of actuators such that one of the plurality of mold
portions moves along the axis from the respective molding position
toward the respective ejecting position while at least one other of
the plurality of mold portions remains stationary relative to the
object in order to at least partially support the object.
Inventors: |
Hendrickson; B. Everett;
(Los Angeles, CA) ; Severn; Craig; (Sharon,
CA) ; McCutcheon; Paul; (Georgetown, CA) ;
Carlson; Timothy; (Arlington, VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Friendship Products LLC |
Arlington |
VA |
US |
|
|
Family ID: |
62782217 |
Appl. No.: |
15/863401 |
Filed: |
January 5, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62442984 |
Jan 6, 2017 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29L 2031/7158 20130101;
B29C 49/4215 20130101; B29K 2067/003 20130101; B29C 49/06 20130101;
B29K 2023/06 20130101; B29C 49/56 20130101; B29K 2667/003 20130101;
B29C 49/6436 20130101; B29K 2823/14 20130101; B29C 35/045 20130101;
B29C 45/372 20130101; B29B 13/024 20130101; B29C 49/786 20130101;
B29C 2049/701 20130101; B29C 49/54 20130101; B29C 49/063 20130101;
B29L 2031/712 20130101; B29C 49/6409 20130101 |
International
Class: |
B29C 49/06 20060101
B29C049/06; B29C 49/42 20060101 B29C049/42; B29C 49/56 20060101
B29C049/56; B29C 45/37 20060101 B29C045/37 |
Claims
1. A system for molding an object, comprising: an articulated mold
having an axis and including a plurality of mold portions
configured to collectively define a molding cavity for shaping the
object when arranged in respective molding positions; a plurality
of actuators, wherein each of the plurality of actuators is
operatively coupled to a respective mold portion of the plurality
of mold portions and configured to move the respective mold portion
along the axis from the respective molding position toward a
respective ejecting position for releasing the object; and a
controller in communication with each of the plurality of actuators
and configured to independently activate each of the plurality of
actuators such that one of the plurality of mold portions moves
along the axis from the respective molding position toward the
respective ejecting position while at least one other of the
plurality of mold portions remains stationary relative to the
object in order to at least partially support the object.
2. The system of claim 1, wherein the molding cavity includes at
least one of a tongue or a groove extending in a direction parallel
to the axis.
3. The system of claim 1, wherein the plurality of actuators are
configured to move the respective mold portions along the axis from
the respective molding positions toward the respective ejecting
positions in a same direction.
4. The system of claim 1, wherein the controller is configured to
activate each of the plurality of actuators sequentially.
5. The system of claim 4, wherein the plurality of mold portions
includes a bottom portion and at least one side portion distributed
along the axis.
6. The system of claim 5, wherein the at least one side portion is
configured to move along the axis from the respective molding
position toward the respective ejecting position prior to the
bottom portion moving along the axis from the respective molding
position toward the respective ejecting position such that the
bottom portion supports the object during movement of the at least
one side portion.
7. The system of claim 4, wherein the plurality of mold portions
includes an upper side portion and a lower side portion distributed
along the axis.
8. The system of claim 7, wherein the lower side portion is
configured to move along the axis from the respective molding
position toward the respective ejecting position prior to the upper
side portion moving along the axis from the respective molding
position toward the respective ejecting position such that the
upper side portion supports the object during movement of the lower
side portion.
9. The system of claim 4, wherein the plurality of mold portions
includes first and second side-by-side portions distributed about
the axis.
10. The system of claim 9, wherein the first side-by-side portion
is configured to move along the axis from the respective molding
position toward the respective ejecting position prior to the
second side-by-side portion moving along the axis from the
respective molding position toward the respective ejecting position
such that the second side-by-side portion supports the object
during movement of the first side-by-side portion.
11. A method of releasing a molded object from a molding cavity
defined by a plurality of mold portions of an articulated mold
having an axis, the method comprising: moving a first mold portion
of the plurality of mold portions along the axis from a respective
molding position toward a respective ejecting position, wherein
during moving the first mold portion the object is supported by a
second mold portion of the plurality of mold portions; and
subsequently moving the second mold portion along the axis from a
respective molding position toward a respective ejecting
position.
12. The method of claim 11, wherein moving the first mold portion
includes activating a first actuator operatively coupled to the
first mold portion.
13. The method of claim 12, wherein moving the second mold portion
includes activating a second actuator operatively coupled to the
second mold portion.
14. The method of claim 11, wherein the first mold portion is
arranged below the second mold portion along the axis when the
first and second mold portions are in the respective molding
positions.
15. The method of claim 11, wherein the first mold portion is
arranged above the second mold portion along the axis when the
first and second mold portions are in the respective molding
positions.
16. The method of claim 11, wherein the first and second mold
portions are arranged side-by-side about the axis when the first
and second mold portions are in the respective molding
positions.
17. A method of manufacturing an object in an articulated mold
having an axis, comprising: arranging a plurality of mold portions
of the articulated mold into respective molding positions to define
a molding cavity; molding the object in the molding cavity; moving
a first mold portion of the plurality of mold portions along the
axis from the respective molding position toward a respective
ejecting position, wherein during moving the first mold portion the
object is supported by a second mold portion of the plurality of
mold portions; and subsequently moving the second mold portion
along the axis from a respective molding position toward a
respective ejecting position.
18. The method of claim 17, wherein moving the first mold portion
includes activating a first actuator operatively coupled to the
first mold portion.
19. The method of claim 18, wherein moving the second mold portion
includes activating a second actuator operatively coupled to the
second mold portion.
20. The method of claim 17, wherein the first mold portion is
arranged below the second mold portion along the axis when the
first and second mold portions are in the respective molding
positions.
21. The method of claim 17, wherein the first mold portion is
arranged above the second mold portion along the axis when the
first and second mold portions are in the respective molding
positions.
22. The method of claim 17, wherein the first and second mold
portions are arranged side-by-side about the axis when the first
and second mold portions are in the respective molding
positions.
23. The method of claim 17, wherein molding the object includes
blow molding the object from a preform.
24. The method of claim 23, wherein blow molding the object
includes stretch blow molding the object from the preform.
25. The method of claim 23, further comprising conditioning the
preform prior to blow molding, wherein conditioning the preform
includes: positioning the preform in a heating cavity; and forcing
a heated gas into the heating cavity onto an exterior surface of
the preform.
26. The method of claim 25, wherein conditioning the preform
further includes positioning a nozzle having at least one sidewall
within the heating cavity to at least partially surround the
preform.
27. The method of claim 26, wherein the at least one sidewall
includes at least one aperture, and wherein forcing the heated gas
into the heating cavity includes directing the heated gas through
the at least one aperture.
28. The method of claim 27, wherein directing the heated gas
through the at least one aperture includes directing the heated gas
to a predetermined portion of the exterior surface of the preform.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 62/442,984, filed Jan. 6, 2017, the
disclosure of which is incorporated by reference herein in its
entirety.
TECHNICAL FIELD
[0002] The present invention relates to devices, systems, and
processes for manufacturing an article such as a plastic bottle or
container using molding techniques, such as blow molding. More
particularly, the present invention relates to devices, systems,
and processes for manufacturing containers that are scalable,
modular, and lockable laterally and vertically with other like
containers.
BACKGROUND
[0003] Blow molding is a well-known technique that is used for
manufacturing plastic articles such as bottles, containers,
automobile parts, or cases. In a one-stage or "single-stage" blow
molding machine, the process begins with manufacture at a first
station of a hot, injection molded preform or "parison" of hollow
plastic material, the preform further conditioned at a second
station and then moved and positioned at a third station which has
a mold cavity with interior walls in the shape of the final article
to be molded. In a "two-stage" machine the preforms are
manufactured externally, but transported to and reheated at a
conditioning station before moving to the blow cavity.
[0004] Injection stretch blow molding (ISBM) is a term of art and
refers mostly, if not entirely, to biaxial PET blow molding from
preforms. ISBM techniques date back only about 35 years. Some
blow-molded plastic bottles are blown from an extruded tube that
the closing mold pinches off at the bottom end. ISBM is used to
provide a plastic container or other useful article of manufacture
created on a machine from a pre-form, which is first stretched in
the axial direction, and then blown in a mold by high pressure air
in the hoop direction. The hot preform may be manufactured via an
injection mold station on a "one-stage" or "single-stage" stretch
blow mold machine, whereafter the preform is temperature
conditioned, and then stretch blow molded into a final article, and
finally cooled on the same machine before ejection.
[0005] Materials used in blow molding to create plastic articles
include polyethylene (PE) and polyethylene terephthalate (PET), due
to their high level of thermoplasticity.
[0006] The typical sequence of operations in a single-stage ISBM
machine is as follows. PET is delivered to the machine site,
usually in small flake form contained in sizeable boxes
("gaylords"). Once the gaylord box is opened, the PET particles
immediately begin absorbing excessive levels of moisture from the
ambient air. Thus, virtually all single-stage ISBM machines run the
PET material through a dryer. The material then enters a "manifold"
meant to maintain PET heat and dryness during transport to the
preform molding station, where the parison is formed by injecting
liquefied PET material into a mold cavity, with parison thickness
and its internal profile a function of the shape of the preform
insertion rod lathed to specifications. Once cooled enough to
transport, the molded preform moves to a conditioning station,
where optimal (e.g., article-specific) pre-blow temperatures are
achieved for the parison, both internally and on its exterior
surface. The conditioned parison then moves to the blow station,
where compressed air works with a stretch rod to expand the PET
resin until contact with the mold cavity walls, at which point the
PET resin quickly cools and hardens, after which the mold is opened
to allow article ejection.
[0007] Manufacturers and other performers of molding techniques are
continuously striving for improvements of such techniques. It would
therefore be desirable to provide improved devices, systems, and
processes for manufacturing an article using molding
techniques.
SUMMARY
[0008] In one embodiment, a system for molding an object includes
an articulated mold having an axis and including a plurality of
mold portions configured to collectively define a molding cavity
for shaping the object when arranged in respective molding
positions. The system also includes a plurality of actuators,
wherein each of the plurality of actuators is operatively coupled
to a respective mold portion of the plurality of mold portions and
configured to move the respective mold portion along the axis from
the respective molding position toward a respective ejecting
position for releasing the object. The system further includes a
controller in communication with each of the plurality of actuators
and configured to independently activate each of the plurality of
actuators such that one of the plurality of mold portions moves
along the axis from the respective molding position toward the
respective ejecting position while at least one other of the
plurality of mold portions remains stationary relative to the
object in order to at least partially support the object. The
molding cavity may include at least one of a tongue or a groove
extending in a direction parallel to the axis. In addition or
alternatively, the plurality of actuators may be configured to move
the respective mold portions along the axis from the respective
molding positions toward the respective ejecting positions in a
same direction.
[0009] In one embodiment, the controller is configured to activate
each of the plurality of actuators sequentially. For example, the
plurality of mold portions may include a bottom portion and at
least one side portion distributed along the axis, and the at least
one side portion may be configured to move along the axis from the
respective molding position toward the respective ejecting position
prior to the bottom portion moving along the axis from the
respective molding position toward the respective ejecting position
such that the bottom portion supports the object during movement of
the at least one side portion. In another embodiment, the plurality
of mold portions may include an upper side portion and a lower side
portion distributed along the axis, and the lower side portion may
be configured to move along the axis from the respective molding
position toward the respective ejecting position prior to the upper
side portion moving along the axis from the respective molding
position toward the respective ejecting position such that the
upper side portion supports the object during movement of the lower
side portion. In yet another embodiment, the plurality of mold
portions may include first and second side-by-side portions
distributed about the axis, and the first side-by-side portion may
be configured to move along the axis from the respective molding
position toward the respective ejecting position prior to the
second side-by-side portion moving along the axis from the
respective molding position toward the respective ejecting position
such that the second side-by-side portion supports the object
during movement of the first side-by-side portion.
[0010] In another embodiment, a method of releasing a molded object
from a molding cavity defined by a plurality of mold portions of an
articulated mold having an axis is provided. The method includes
moving a first mold portion of the plurality of mold portions along
the axis from a respective molding position toward a respective
ejecting position, wherein during moving the first mold portion the
object is supported by a second mold portion of the plurality of
mold portions. The method further includes subsequently moving the
second mold portion along the axis from a respective molding
position toward a respective ejecting position. In one embodiment,
moving the first mold portion includes activating a first actuator
operatively coupled to the first mold portion. Moving the second
mold portion may include activating a second actuator operatively
coupled to the second mold portion.
[0011] In one embodiment, the first mold portion is arranged below
the second mold portion along the axis when the first and second
mold portions are in the respective molding positions. In another
embodiment, the first mold portion is arranged above the second
mold portion along the axis when the first and second mold portions
are in the respective molding positions. In yet another embodiment,
the first and second mold portions are arranged side-by-side about
the axis when the first and second mold portions are in the
respective molding positions.
[0012] In another embodiment, a method of manufacturing an object
in an articulated mold having an axis is provided. The method
includes arranging a plurality of mold portions of the articulated
mold into respective molding positions to define a molding cavity
and molding the object in the molding cavity. The method also
includes moving a first mold portion of the plurality of mold
portions along the axis from the respective molding position toward
a respective ejecting position, wherein during moving the first
mold portion the object is supported by a second mold portion of
the plurality of mold portions. The method further includes
subsequently moving the second mold portion along the axis from a
respective molding position toward a respective ejecting position.
In one embodiment, moving the first mold portion includes
activating a first actuator operatively coupled to the first mold
portion. Moving the second mold portion may include activating a
second actuator operatively coupled to the second mold portion.
[0013] In one embodiment, the first mold portion is arranged below
the second mold portion along the axis when the first and second
mold portions are in the respective molding positions. In another
embodiment, the first mold portion is arranged above the second
mold portion along the axis when the first and second mold portions
are in the respective molding positions. In another embodiment, the
first and second mold portions are arranged side-by-side about the
axis when the first and second mold portions are in the respective
molding positions.
[0014] The step of molding the object may include blow molding the
object from a preform. For example, blow molding the object may
include stretch blow molding the object from the preform. The
method may further include conditioning the preform prior to blow
molding, wherein conditioning the preform includes positioning the
preform in a heating cavity and forcing a heated gas into the
heating cavity onto an exterior surface of the preform.
Conditioning the preform may further include positioning a nozzle
having at least one sidewall within the heating cavity to at least
partially surround the preform. The at least one sidewall may
include at least one aperture, and forcing the heated gas into the
heating cavity may include directing the heated gas through the at
least one aperture. For example, directing the heated gas through
the at least one aperture may include directing the heated gas to a
predetermined portion of the exterior surface of the preform.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Various additional features and advantages of the invention
will become more apparent to those of ordinary skill in the art
upon review of the following detailed description of one or more
illustrative embodiments taken in conjunction with the accompanying
drawings. The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate one or more
embodiments of the invention and, together with the general
description given above and the detailed description given below,
serve to explain the one or more embodiments of the invention.
[0016] FIG. 1 is a perspective view of a modular interlocking
container manufactured in accordance with an embodiment of the
invention.
[0017] FIG. 2 is a cross sectional view of a heating station,
showing heated air directed therein during a conditioning
operation, in accordance with an embodiment of the invention.
[0018] FIG. 3 is a cross sectional view of a molding station,
showing mold portions of an articulated mold in respective molding
positions in accordance with an embodiment of the invention.
[0019] FIG. 4 is a partial cross sectional view of the molding
station of FIG. 3, showing pressurized gas directed therein during
a blow molding operation.
[0020] FIG. 5 is a partial cross sectional view of the molding
station of FIG. 3, showing a side mold portion being retracted
during a demolding operation.
[0021] FIG. 6 is a view similar to FIG. 5, showing a bottom mold
portion and the side mold portion being retracted during the
demolding operation.
[0022] FIG. 7 is a view similar to FIG. 6, showing the bottom and
side mold portions in respective ejecting positions and top mold
portions being retracted during the demolding operation.
[0023] FIG. 8 is a view similar to FIG. 7, showing the bottom,
side, and top mold portions in respective ejecting positions and
the carrying apparatus releasing the blow molded container during
the demolding operation.
[0024] FIG. 9 is a view similar to FIG. 8, showing the container
dropping to a collection ramp during the demolding operation.
[0025] FIG. 10 is a partial cross sectional view of an alternative
molding station, showing a lowermost horizontal section of a side
mold portion being retracted during a demolding operation in
accordance with an embodiment of the invention.
[0026] FIG. 11 is a view similar to FIG. 10, showing middle and
uppermost horizontal sections of the side mold portion being
retracted during the demolding operation.
[0027] FIG. 12 is a view similar to FIG. 11, showing a bottom mold
portion and the horizontal sections being retracted during the
demolding operation.
[0028] FIG. 13 is a partial cross sectional view of an alternative
molding station, showing a first vertical section of a side mold
portion being retracted during a demolding operation in accordance
with an embodiment of the invention.
[0029] FIG. 14 is a view similar to FIG. 13, showing second and
third vertical sections of the side mold portion being retracted
during the demolding operation.
[0030] FIG. 15 is a view similar to FIG. 14, showing a bottom mold
portion and the vertical sections being retracted during the
demolding operation.
DETAILED DESCRIPTION
[0031] While the exemplary embodiments are described below for use
in a stretch blow molding procedure, it will be understood by those
skilled in the art that the embodiments described herein could be
used in other molding or die casting applications, including but
not limited to extrusion blow molding, injection molding, or tumble
molding.
[0032] As used herein, relational terms such as first and second,
top and bottom, and the like may be used solely to distinguish one
entity or action from another entity or action without necessarily
requiring or implying any actual such relationship or order between
such entities or actions. The terms "comprises," "comprising," or
any other variation thereof, are intended to cover a non-exclusive
inclusion, such that a process, method, article, or apparatus that
comprises a list of elements does not include only those elements
but may include other elements not expressly listed or inherent to
such process, method, article, or apparatus. An element proceeded
by "comprises . . . a" does not, without more constraints, preclude
the existence of additional identical elements in the process,
method, article, or apparatus that comprises the element.
[0033] The embodiments of the invention include systems, devices,
and processes for manufacturing a scalable, modular,
interconnective, and interlocking container with multi-purpose uses
and applications such as that described in U.S. patent application
Ser. No. 14/777,210 ("the '210 application"), filed Sep. 15, 2015,
the disclosure of which is incorporated by reference in its
entirety. An exemplary first use of such a container is for
transporting and/or storing flowable materials such as liquids or
pourable solids. An exemplary second use of such a container is for
a creative modeling element or for a sturdy, low cost, easily
assembled building block material of a standardized nature. The
embodiments can be used for building housing, storage, or other
practical structures, including applications employed for disaster
relief, humanitarian development projects, for military or defense
purposes, and for other practical and modeling purposes. The
embodiments include systems, devices, and processes for
manufacturing a single container that is interlocked to other
modular containers of the same or different sizes. Each modular
container slide-locks with other containers to form strong wall and
building structures that can be filled with liquids such as water,
natural earth, sand, or other natural or processed materials,
thereby forming a sturdy structure without need of mortar, and can
adapt to uneven base surfaces typically found in natural
terrain.
[0034] Referring now to FIG. 1, an exemplary scalable, modular
interconnecting container 10 is a hollow or partially hollow
element that may be constructed of plastic, metal, resin, or
composites. For example, in certain embodiments, the container is
made of PE, PET and/or other thermoplastic material. Alternatively,
the container 10 may be constructed of any rigid material that is
appropriately high-strength and capable of providing sufficient
stackable and connectable rigidity. The container 10 includes a
plurality of upright walls 12. In the embodiment illustrated in
FIG. 1, the container 10 is shown with eight longitudinal walls 12
of equal or varying height which form a generally octagonal
latitudinal cross-section. In other embodiments, the container 10
may be formed with differently shaped latitudinal cross-sections,
such as circular, ovoid, polygonal, triangular, square,
rectangular, or hexagonal shapes, for example. In any event, the
container 10 may be configured to hold a liquid, solid, and/or gas
and may also be configured for use as a modeling or building
element with or without any internal contents.
[0035] As shown, the container 10 includes a top end section 14
which includes a neck 16 terminating at an aperture 18 for filling
the container 10 with any gas, fluid, granular, flake, or other
material. In one embodiment, the container 10 may be manufactured
with an airtight or pressure-resistant seal or cap (not shown). The
neck 16 is configured to couple with such a cap via threads 20
provided on the neck 16 for sealing the contents within the
container 10. Alternatively, the neck 16 may be configured to
couple with a cap via a snap-fit mechanism, or any other suitable
type of connection for forming an appropriate seal to prevent the
contents of the container 10 from leaking out thereof and/or to
prevent foreign objects from entering the container 10. With an
appropriate seal formed between the neck 16 and the cap, the
container 10 may be made fluid-tight for holding and transporting
liquids (e.g., water, juice, cooking oil), or could form an
appropriate seal for granulated or powdered goods (e.g., grains,
seeds, flour, flakes), household materials (e.g., soap, cleaners),
or construction materials (e.g., cement, grout, sand). As shown, a
ring 22 is formed near the base of the neck 16 and may provide a
seat for a tamper evident ring (not shown) that may be positioned
between the base of the neck 16 and the threads 20, as may be
desired.
[0036] The illustrated container 10 includes a bottom end section
24 including a vertical interconnection receptor 25 (FIG. 4) formed
as an indent therein having a cross dimension sized to receive a
closure cap and ring 22 from a similar, second container 10. The
receptor 25 may have a limiting edge with a cross dimension sized
to engage with the ring 22 during vertical interconnection with the
similar second container 10 to provide a stop therewith.
[0037] In the embodiment shown, the container 10 provides a
mechanism for lateral connection with other containers 10 in a
slidable, interlocking manner. For example, lateral connection of
multiple containers 10 may be enabled by tongues 26 and grooves 28
distributed in multiple locations laterally on or within the walls
12 of the container 10. In this regard, each tongue 26 is
configured as a raised, flat and/or slightly rounded protrusion
formed on or within a respective wall 12. Each groove 28 is
indented into a respective wall 12 and configured to receive a
corresponding tongue 26 from a second container 10 having similar
connectivity features. In one embodiment, the tongues 26 and
grooves 28 are formed along the walls 12 in a generally
perpendicular orientation to the top and bottom sections 14, 24. As
shown, the tongues 26 and grooves 28 may be positioned in
alternating locations around the container 10, wherein a tongue 26
is positioned on every alternating wall 12 with a groove 28
positioned on every wall 12 therebetween. Alternatively, one or
more tongues 26 could be formed on one or more of the walls 12 and
one or more grooves 28 could be formed on the remaining walls 12.
In other embodiments, a container 10 may have only grooves 28 on
its respective side walls 12 while other containers 10 may have
only tongues 26 formed in their respective side walls 12.
Regardless of the distribution patterns, separate containers 10 can
be interlocked with each other via the tongues 26 and grooves
28.
[0038] To that end, an interlocking mechanism is provided using
undercuts 30 of each tongue 26 that may be received into
corresponding expanded cuts 32 of each groove of a similar, second
container 10. Together with their respective tongues 26 and/or
grooves 28, the undercuts 30 and/or expanded cuts 32 may be
referred to as "dovetails." The undercuts 30 are formed such that
each tongue 26 interfaces with the respective wall 12 with a
narrower base than the width of the tongue 26 at its outermost
portion. Similarly, the width of each groove 28 including the
respective expanded cuts 32 is greater than the width of each
groove 28 excluding the respective expanded cuts 32 such that when
two containers 10 are connected via longitudinal sliding of a
tongue 26 into a corresponding groove 28, the width of the outer
edges of the tongue 26 lock laterally behind each respective
expanded cut 32. It will be appreciated that each container 10 may
include any number of tongues 26 and/or grooves 28 in order to
interconnect, as may be desired. In one embodiment, the
configuration of the container, including any of the tongues 26,
grooves 28, undercuts 30, and/or expanded cuts 32 may be similar to
those described in the '210 application.
[0039] Referring now to FIG. 2, a preform 34 may be used to form
the container 10. The preform 34 may be similar to that described
in the '210 application. For example, the preform 34 may be formed
via injection blow molding in a preform mold cavity (not shown) as
a closed-end cylindrical article generally similar in shape to a
test-tube. As shown, the preform 34 is initially formed with the
neck 16, opening 18, threads 20, and ring 22 of the final container
10, along with a generally cylindrical body 36. As described in
greater detail below, during the stretch blow mold process, the
cylindrical body 36 may be expanded to conform to the interior
walls of a mold, while the neck 16 may remain substantially the
same in shape, size, and configuration. In the embodiment shown,
the cylindrical body 36 terminates at a closed end 38 which
includes include a protruding tip 40 that is an artifact of the
injection process. The thicknesses of the cylindrical body 36
and/or closed end 38 may vary by design or by artifact. For
example, the closed end 38 may have a greater thickness than that
of the cylindrical body 36 in order to facilitate plastic flow into
a lower portion of a mold, as described in greater detail
below.
[0040] In any event, the preform 34 may be subjected to an ISBM
technique, such as a hot parison technique, wherein after formation
the preform 34 is immediately transferred to a conditioning station
where the potential heat within the preform 34 gained during the
injection mold process can be utilized and fine-tuned for ISBM
operation to produce the container 10. In this regard, the
distribution of heat in the hot closed-end preform 34 may
significantly influence the wall thickness and plastic flow of the
final blown container 10. Thus, irregularity in temperature of the
preform 34 can cause defects in the final blown container 10. For
example, such irregularities may lead to undesirably thin walls of
a portion of the container 10 and/or the inability of the material
to properly flow in a mold due to cooling and hardening of the
material. This may be particularly problematic for molds having
complex geometries such as deep and/or narrow crevasses into which
the material is desired to flow in order to form features such as
the dovetails of the container 10.
[0041] With continuing reference to FIG. 2, in one embodiment, an
exemplary conditioning or heating station 42 for heating the
exterior surface of the preform 34 is provided that overcomes
certain problems or shortcomings of conventional preform heating
stations, particularly when used to manufacture articles having
complex geometries such as the dovetails of the interlocking
container 10. For example, it will be appreciated that conventional
preform heating stations are typically not capable of heating the
exterior of the preform 34 to sufficiently high temperatures needed
to blow the preform 34 into a mold having complex geometries to
form features such as the dovetails of the container 10.
Conventional preform heating stations are also not able to
precisely measure the heat and are not able to precisely adjust the
heat transferred to the exterior of the preform 34 from the heating
station. In addition, conventional preform heating stations are not
able to heat the exterior of the preform 34 evenly and not able to
direct heat to specific areas on the exterior of the preform 34
where more material flow is desired in the next stage of the blow
mold process.
[0042] The exemplary heating station 42 is capable of meeting the
challenges present in making the container 10 with the dovetails
and which are not typically present in manufacturing conventional
articles such as conventional containers. In this regard, the
container 10 may be particularly sensitive to the heating
temperature, and it may be desirable to provide a very high heat to
the exterior of the preform 34 in the preform heating stage in
order to allow the material to flow into the dovetails and/or
vertical interconnector receptor 25. The difference in wall
thickness from one side of the container 10 to the other may impact
the strength of the dovetail connections and therefore impact
function significantly. The difference in wall thickness from the
top of the container 10 to the bottom of the container 10 may
impact the strength of container 10 and therefore impact stability
of the container 10. For example, weaknesses in the wall thickness
may lead to blowouts during blow molding. The features and
characteristics of the container 10 vary significantly from top to
bottom and side to side, such as due to the dovetails and vertical
receptor.
[0043] The exemplary heating station 42 is configured to heat the
exterior of the preform 34 in preparation for blow molding. More
particularly, the heating station 42 includes a manifold 44
defining a heating cavity 46 for receiving the preform 34 and a
heater 48 in thermal communication with the heating cavity 46 and
configured to heat a suitable gas, such as air. In one embodiment,
the heating station 42 may further include a carrying apparatus 49
configured to securely grip the neck 16 of the preform 34 external
to the heating cavity 46 with the cylindrical body 36 of the
preform 34 positioned within the heating cavity 46. In this regard,
the carrying apparatus 49 includes first and second arms 50, 52
each having grooves or threads 53 for mating with the threads 20 of
the neck 16 when the neck 16 is clamped between the first and
second arms 50, 52. As shown, the first and second arms 50, 52 are
carried by first and second supports 54, 56, respectively. As
discussed in greater detail below, the arms 50, 52 and/or supports
54, 56 may be movable in order to grip, release, and/or transport
the preform 34 between the heating station 42 and other stations
for performing the blow molding procedure. A core rod 57 may extend
from the carrying apparatus 49 down into the interior of the
preform 34 to support the preform 34. In one embodiment, the core
rod 57 may assist in heating and/or maintaining the temperature of
the preform 34. For example, the core rod 57 may be heated to
approximately 60.degree. C. In one embodiment, the core rod 57 may
only be inserted into the preform 34 during a portion of the time
period when the preform 34 is conditioned at the preform heating
station 42. For example, the core rod 57 may be inserted into the
preform 34 for approximately 3 seconds, while the cylindrical body
36 of the preform 34 may be positioned within the heating cavity 46
for approximately 10 seconds.
[0044] The heating station 42 further includes a blower 58
configured to force the gas heated by the heater 48 into the
heating cavity 46, as indicated by the arrows A1, and onto the
exterior of the preform 34. Thus, the heating station 42 uses
forced hot air to heat the exterior of the preform 34 in the
heating cavity 46, unlike conventional heating or conditioning
stations that typically utilize radiant heat. By forcing hot air
onto the exterior of the preform 34, the exemplary heating station
42 allows for heating the exterior of the preform 34 faster and
more thoroughly than the conventional radiant heating method. The
heating station 42 may also provide the capability to heat the
exterior of the preform 34 to a higher temperature in a shorter
amount of time in comparison to the conventional radiant heating
method. In one embodiment, the temperature of the hot air in the
heating cavity 46 at or near the exterior of the preform 34 may be
between approximately 200.degree. C. and approximately 600.degree.
C. For example, the temperature of the hot air may be between
approximately 285.degree. C. and approximately 315.degree. C. In
one embodiment, the temperature of the hot air may be approximately
300.degree. C. In addition or alternatively, the heating station 42
may be configured to expose the preform 34 to the hot forced air
for approximately 10 seconds. Such a 10 second period may be
substantially the entire period during which the cylindrical body
36 of the preform 34 is within the heating chamber 46. In one
embodiment, the pressure of the hot air blown onto the exterior of
the preform 34 may be approximately 20 PSI. A portion of hot air
may escape between the neck 16 of the preform 34 and the arms 50,
52.
[0045] In one embodiment, the exemplary heating station 42 may be
configured to direct forced, hot air to specific points on the
exterior of the preform 34, unlike the conventional heating
stations wherein the radiant heat is not capable of targeting
specific areas that may require increased heating to allow
effective blow molding. In this regard, temperature differentials
in the mold wall(s) may undesirably cool certain portions of the
blown preform prior to others unless counteracted by increased
heating of the preform 34 at corresponding locations. Similarly,
the dovetails formed as the preform 34 is blown may cool faster as
a result of protruding beyond the inner wall of the mold and
interfacing with a relatively thin outer wall of the mold. In
certain embodiments, the closed end 38 of the preform 34 may be
required to flow farther than the cylindrical body 36 of the
preform 34 in order to flow into the dovetails at the bottom of the
mold, but may cool prior to filling the dovetails due to contact
with the bottom wall of the mold. Thus, it may be desirable to
target heat to specific areas of the exterior of the preform 34 to
prevent premature cooling of such areas in the mold and to maintain
the preform 34 in an appropriate temperature-regulated plasticized
state prior to stretch blow molding.
[0046] To that end, the illustrated heating station 42 includes a
nozzle 60 including a cylindrical sidewall or shell 62 and
positioned within the heating cavity 46 to at least partially
surround the preform 34. The nozzle 60 provides for targeted
heating of specific areas on the exterior of the preform 34. In
this regard, the sidewall 62 of the nozzle 60 includes a plurality
of apertures, such as bores 64, for directing gas therethrough. For
example, hot forced air may be directed through the bores 64 in the
sidewall 62 by the blower 58 to predetermined areas or portions of
the exterior of the preform 34 where increased heating is desired.
In one embodiment, the bores 64 may have a cross dimension, such as
a diameter, of between approximately 0.200 inch and approximately
0.205 inch. While generally circular bores 64 are shown, apertures
of other embodiments may include slots, curves, funnels, or any
suitable type and/or shape of aperture capable of directing the
forced hot air to a specific or targeted area of the exterior of
the preform 34 inside of the heating cavity 46. The nozzle 60 may
partially or fully surround the preform 34 in the heating cavity 46
and may direct hot air to a portion of the preform 34 at any
desirable location on the exterior of the preform 34. In addition
or alternatively, the bores 64 may be adjustable, such as in
position, cross dimensional size and/or shape. For example, the
bores 64 may be opened and closed, moved, or redirected in order to
direct hot air toward areas on the exterior of the preform 34 where
more heat is desired and/or direct hot air away from areas on the
exterior of the preform 34 where less heat is desired to accomplish
desired flow results in the next blow stage.
[0047] In one embodiment, the bores 64 are arranged in a uniform
pattern on the sidewall 62 of the nozzle 60 to provide an even heat
distribution around the nozzle 60. The bores 64 may be arranged in
a pattern that minimizes total temperature differences and
maximizes uniformity. In this regard, the pattern of the bores 64
may be altered from that illustrated in order to encourage the
forced air flow to move in such a way as to smooth out any
temperature gradients. In another embodiment, the bores 64 may be
arranged to provide a differential application of heat around the
circumference of the nozzle. The particular locations of the bores
64 may correspond to the locations of various geometrical features
on the blown container 10, such as the dovetails.
[0048] The nozzle 60 may be configured to provide clearance between
the preform 34 and the sidewall 62 of the nozzle 60 when the
preform 34 is inserted into the heating cavity 46 and at least
partially surrounded by the nozzle 60. For example, the outer
diameter of the cylindrical body 36 of the preform 34 may be
approximately 24 mm and the inner diameter of the cylindrical
sidewall 62 of the nozzle 60 may be approximately 34.5 mm, thereby
providing a clearance of approximately 5.25 mm between the preform
34 and the sidewall 62.
[0049] Thus, the heating station 42 may precisely direct more heat
toward areas on the exterior of the preform 34 where additional
flow is desired in the next blow stage of the blow mold procedure
and precisely avoid heating those areas on the exterior of the
preform 34 where additional flow in the next blow stage of the blow
mold procedure is not desired.
[0050] It will be appreciated that the containers 10 and/or preform
34 may require being heated to a significantly higher temperature
than conventional containers. In some embodiments, the temperatures
desired in the blow molding process may reach the limits of what
the preform 34 can be heated to without beginning to melt or
otherwise deform in the heating station 42. For example, the
temperature of the hot air forced onto the exterior of the preform
34 may approach the melting temperature of the material of the
preform 34. Such deformation could prevent the container 10 from
being properly blow molded. Therefore, it may be desirable to be
able to precisely, by very small increments, increase the
temperature of the air being blown on the exterior of the preform
34 to the point where the desired flow of material in the blow
molding process is achieved without deforming the preform 34.
[0051] To that end, the heating station 42 may be configured to
precisely adjust as well as measure the temperature of the hot air
being forced onto the exterior of the preform 34. In this regard,
the heating station 42 includes a temperature controller 66 in
communication with the heater 48 and a temperature gauge 68 in
communication with the temperature controller 66. The temperature
controller 66 is configured to adjust the output of the heater 48,
and thereby the temperature of the air forced onto the exterior of
the preform 34, and the temperature gauge 68 is configured to
measure the temperature of the hot air being blown onto the
exterior of the preform 34. For example, the temperature gauge 68
may be positioned in the heating cavity 46 proximate the exterior
of the preform 34 in order to precisely measure the temperature of
the air blown thereon. In one embodiment, the temperature gauge 68
may be positioned within the nozzle 60. In any event, the
temperature gauge 68 may be configured to send a signal to the
temperature controller 66 indicative of the temperature
measurement, which the temperature controller 66 may use to
determine a proper output of the heater 48 and adjust the output of
the heater 48 accordingly. In this manner, the temperature
controller 66 and temperature gauge 68 may provide precise
measurement of the temperature of the air being blown on the
exterior of the preform 34, and precise adjustment of the
temperature of the air being blown on targeted or specific areas of
the exterior of the preform 34.
[0052] Turning now to FIGS. 3-9, in one embodiment, an exemplary
blow mold station 70 for molding a finished article such as the
container 10 from the preform 34 is provided that overcomes various
problems and/or shortcomings of conventional blow molding stations.
As discussed in greater detail below, the blow mold station 70 is
configured to mold the preform 34 into the finished shape of the
container 10, including the dovetails. The blow mold station 70
meets the various challenges present in making the container 10
that may not typically be present in making conventional articles
such as conventional containers. In this regard, conventional
articles such as conventional containers are typically extracted
from a mold in an injection stretch blow mold machine via a
clamshell opening process. The container 10 may not be suitable for
extraction from a mold via a clamshell opening process due to the
undercuts 30 and expanded cuts 32 of the dovetails, for example. In
one embodiment, the exemplary blow mold station 70 may be capable
of extracting various interlocking articles that include deeper
undercuts 30 and expanded cuts 32 on the tongues 26 and grooves 28
than those described in the '210 application.
[0053] In one embodiment, the exemplary blow mold station 70 may be
used in conjunction with the exemplary heating station 42 so that
during the blow mold process, material flows to a better degree
into the deeper crevasses of the dovetails. For example, the
heating station 42 may be configured as a separate apparatus that
can be modified to attach onto, and become operationally integrated
with, the blow mold station 70. In other words, the heating station
42 may be operationally synchronized with the process of the blow
mold station 70 to heat a preform 34 prior to the preform 34 being
automatically moved to the blow mold station 70 to be blow molded.
Such modularity may enable upgrading existing blow mold stations
70, for example.
[0054] It will be appreciated that various challenges and
difficulties in the demolding process may be present, such as when
manufacturing the container 10 after subjecting the associated
preform 34 to the exemplary preform heating station 42. For
example, due to the heating processes at the preform heating
station 42 successfully assisting material to flow into and/or
around the dovetail portions during the blowing step, the
containers 10 may be "grabbed" more strongly by the at least a
portion of the mold as the mold is lowered to remove the container
10 following the blow stage due to the static friction between the
container 10 and the mold. As a result, the container 10 may be
undesirably deformed or destroyed while being extracted from the
mold. Such deformations may include areas on or around the neck 16
of the container 10 that may become stretched as a result of the
neck 16 being held firmly in place while the walls 12 of the
container 10 may be pulled down by the withdrawing mold or mold
portion due to the static friction therebetween. The resulting
tension may stretch the neck 16 rendering the container 10 unusable
and/or tearing the container 10 into separate pieces. As discussed
below, the exemplary blow mold station 70 may be configured to
address one or more of these issues.
[0055] In the embodiment shown, the blow mold station 70 includes
an articulated mold 72 having a plurality of mold portions
configured to collectively define a molding cavity 74 for molding
the preform 34 into a finished article such as the container 10
when arranged in respective molding positions (FIG. 3). More
particularly, the illustrated articulated mold 72 includes a bottom
mold portion 76, a generally cup-shaped side mold portion 78, and
first and second top mold portions 80, 82. The articulated mold 72
has a longitudinal axis L along which the bottom mold portion 76,
side mold portion 78, and top mold portions 80, 82 are distributed.
In the embodiment shown, the side mold portion 78 includes at least
one dovetail 84 including a tongue or a groove extending in a
direction parallel to the axis L for forming a corresponding
dovetail on the container 10.
[0056] As shown, the bottom mold portion 76 is mounted at a bottom
end thereof to a bottom mold platform 86 having a pair of apertures
88 extending therethrough, the purposes of which are discussed
below. The side mold portion 78 is mounted at a bottom end thereof
to a side mold platform 90 having a generally central aperture 92
through which the bottom mold portion 76 extends. In the embodiment
shown, the side mold platform 90 may itself provide a molding
surface for the container 10. The first and second top mold
portions 80, 82 are mounted at outer sides thereof to first and
second top mold platforms 94, 96, respectively. In certain
embodiments, any of the mold portions 76, 78, 80, 82 may be
integrally formed with their respective platforms 86, 90, 94, 96 as
unitary pieces.
[0057] In the illustrated blow mold station 70, the carrying
apparatus 49 previously described with respect to the heating
station 42 is configured to securely grip the neck 16 of the
preform 34 external to the molding cavity 74 with the cylindrical
body 36 of the preform 34 positioned within the molding cavity 74.
In this regard, the carrying apparatus 49 may be configured to move
(e.g., rotate and/or translate) from the heating station 42 to the
blow mold station 70 in order to automatically transport the
preform 34 from the heating cavity 46 to the molding cavity 74. In
this manner, the heating station 42 may be integrated with the blow
mold station 70. In another embodiment, the blow mold station 70
may include a dedicated carrying apparatus (not shown).
[0058] In any event, the blow mold station 70 also includes a
compressed gas conduit 98 and nozzle 100 configured to at least
partially extend into the neck 16 of the preform 34 for directing
compressed gas, such as air, into the preform 34 for blow molding
the preform 34 into the final shape of the container 10, as
indicated by the arrows A2 (FIG. 4). A stretch rod 102 terminating
at a stretch rod tip 104 extends through the conduit 98 and nozzle
100, and is configured to lower the stretch rod tip 104 into the
preform 34 in order to stretch the preform 34 into the molding
cavity 74. In one embodiment, the preform 34 may be stretched by
the stretch rod 102 and/or stretch rod tip 104 into the molding
cavity 74 to the bottom mold portion 76 (whereat the protruding tip
40 may interact with the bottom mold portion 76 to assist in
centering the preform 34 in the molding cavity 74) and may be
subjected to pressurized gas directed to the interior of the
preform 34 via the compressed gas conduit 98 and nozzle 100. For
example, the pressure of the gas directed into the interior of the
preform 34 may be approximately 585 PSI. In one embodiment, the
stretching of the preform 34 by the stretch rod 102 and/or stretch
rod tip 104 and the blowing of the preform 34 by the compressed gas
may occur substantially simultaneously.
[0059] After blow molding the container 10, the exemplary blow mold
station 70 is configured to provide effective and efficient
demolding of the finished container 10 with a minimal risk of
damage to the container 10, including the neck 16 and the dovetails
including the tongues 26 and grooves 28. In the embodiment shown,
each of the mold portions 76, 78, 80, 82 and arms 50, 52 are
independently movable. More particularly, the bottom and side mold
portions 76, 78 are independently movable along the axis L, and the
top mold portions 80, 82 and arms 50, 52 are independently movable
radially relative to the axis L. In this regard, the blow mold
station 70 includes a plurality of actuators, such as hydraulic
actuators 110, each operatively coupled to a respective mold
portion 76, 78, 80, 82 or arm 50, 52. Each illustrated actuator 110
includes a cylinder 112 and a piston 114 expandable from and/or
retractable into the respective cylinder 112 and coupled to one of
the platforms 86, 90, 94, 96 or arms 50, 52 at a distal end
thereof. In the embodiment shown, the pistons 114 coupled to the
side mold platform 90 extend through the apertures 88 of the bottom
mold platform 86 in order to reach the side mold platform 90. While
hydraulic actuators 110 are shown, it will be appreciated that any
suitable actuators, such as pneumatic actuators or translation
screw actuators, may be used.
[0060] The blow mold station 70 includes a controller 120 in
communication with each of the actuators 110 and configured to
independently activate each of the actuators 110 to retract the
respective mold portions 76, 78, 80, 82 and arms 50, 52 during the
demolding process and, more particularly, to "pull down" the bottom
and side portions 76, 78 independently during the demolding
process. In this regard, the controller 120 may be configured to
activate the actuators 110 of each of the platforms 86, 90, 94, 96
and/or supports 54, 56 sequentially. For example, the controller
120 may initially activate the actuators 110 of the side mold
portion 78 to retract the respective pistons 114 in order to move
the side mold portion 78 downward along the axis L from the
respective molding position toward a respective ejecting position,
as indicated by the arrows A3 (FIG. 5). As the side mold portion 78
moves toward the respective ejecting position, the inner surface of
the aperture 92 of the side mold platform 90 may traverse along an
outer surface of the bottom mold portion 76. The controller 120 may
subsequently activate the actuators 110 of the bottom mold portion
76 to retract the respective pistons 114 in order to move the
bottom mold portion 76 downward along the axis L from the
respective molding position toward a respective ejecting position
(FIG. 6). In the embodiment shown, the controller 120 is configured
to activate the actuators 110 of the bottom mold portion 76 when
the side mold platform 90 contacts or is in near contact with the
bottom mold platform 86. In this manner, the bottom and side mold
portions 76, 78 may move together toward the respective ejecting
positions when the side mold platform 90 reaches the bottom mold
platform 86, as indicated by the arrows A4. Alternatively, the
bottom mold portion 76 may begin to move toward the respective
ejecting position substantially immediately after the side mold
portion 78 begins moving and overcomes the static friction with the
container 10.
[0061] The bottom mold portion 76 may thus provide support to the
blown container 10 for a predetermined amount of time at least
until the static friction is overcome between the container 10 and
the side mold portion 78. Once the static friction is overcome and
the side mold portion 78 is moving down, any friction between the
container 10 and the side mold portion 78 is kinetic. Such kinetic
friction may be lower than the static friction previously present
between the container 10 and the side mold portion 78. More
particularly, this kinetic friction may be sufficiently low such
that the bottom mold portion 76 may be moved down without causing
the container 10 to stretch beyond normal limits associated with
damage or rupture.
[0062] In other words, after the static friction between the
container 10 and side mold portion 78 is overcome, the kinetic
friction between the container 10 and the moving side mold portion
78 may be insufficient to deform or destroy the container 10. The
support from the bottom mold portion 76 may assist in preventing
the container 10 from stretching beyond its limit and/or being
broken apart during the demolding process. In this manner, the side
mold portion 78 may begin the demolding process before the bottom
mold portion 76 is pulled down.
[0063] With the bottom and side mold portions 76, 78 moved toward
or in their respective ejecting positions, the top mold portions
80, 82 may be moved via the controller 120 and respective actuators
110 laterally away from the axis L in opposite directions, as
indicated by the arrows A5 (FIG. 7). Similarly, the first and
second arms 50, 52 may be moved via the controller 120 and
respective actuators 110 laterally away from the axis L in opposite
directions, as indicated by the arrows A6, to release the container
10 and allow the container 10 to drop, as indicated by the arrow A7
(FIG. 8). In the embodiment shown, the container 10 is dropped onto
a collection ramp 122, as indicated by the arrow A8 (FIG. 9) which
may direct the container 10 to a collection bin (not shown). When
the container 10 has exited the blow mold station 70, the
controller 120 may be configured to activate the actuators 110 to
expand the respective pistons 114 in order to move the respective
mold portions 76, 78, 80, 82 in directions opposite those discussed
above to thereby return each of the mold portions 76, 78, 80, 82 to
their respective molding positions. For example, the controller 120
may activate the actuators 110 of the mold portions 76, 78, 80, 82
simultaneously to return each of the mold portions 76, 78, 80, 82
to their respective molding positions for performing a subsequent
molding operation.
[0064] In one embodiment, the actuators 110 and/or controller 120
allow for multiple, sequential, coordinated and/or timed movements
of the bottom and side mold portions 76, 78 along the axis L to
enable the bottom and side mold portions 76, 78 to be pulled down
sequentially, in tandem, and/or discreetly. Such coordination may
allow for removal of the container 10 even when configured with
deeply blown undercuts 30 and/or expanded cuts 32 without deforming
or destroying the container 10 due to excessive friction or other
strong side-to-side connections otherwise caused by such deeply
blown undercuts 30 and/or expanded cuts 32.
[0065] The controller 120 may be configured with timing software
and/or hardware for coordinating activation of the various
actuators 110. For example, the controller 120 may include
instructions for software and a microprocessor (not shown) to
execute the instructions for operating and/or synchronizing the
actuators 110. In one embodiment, the controller 120 may be
configured to synchronize the actuators 110 with other components
and/or processes of the blow mold station 70 or blow molding
procedure for fast and efficient production.
[0066] For example, there is limited time between the different
blow mold process stages. Therefore, the sequential "pulls" for the
various mold portions 76, 78, 80, 82 must be accomplished within
the window of time allotted for the pull stage of the blow mold
machine process. Coordinating and timing the activation of the
actuators 110 to move the respective mold portions 76, 78, 80, 82
toward the ejecting positions efficiently within that window may
allow for using the minimum amount of time required to sequentially
overcome the static friction which then minimizes the overall cycle
time, thereby lowering the manufacturing costs of each container 10
and increasing productivity.
[0067] In one embodiment wherein the preform heating station 42 and
blow molding station 70 are integrated with a preform forming
(e.g., injection molding) station for initially forming the preform
34 (not shown), carrying apparatus 49 may transport the formed
preform 42 from the preform forming station to the preform heating
station 42 and position the cylindrical body 36 of the preform 34
in the heating cavity 46. The core rod 57 may substantially
simultaneously be lowered into the preform 34. The cylindrical body
36 of the preform 34 may be maintained within the heating cavity 46
for approximately 10 seconds. Hot air may be directed to the
exterior of the preform 34 for substantially the entirety of this
approximately 10 second period, with the temperature of hot air
being between approximately 285.degree. C. and approximately
310.degree. C. and the pressurization of the hot air being
approximately 20 PSI. The carrying apparatus 49 may then transport
the conditioned preform 34 to the blow mold station 70 and position
the cylindrical body 36 of the preform 34 in the molding cavity 74.
The stretch rod 102 may be lowered to stretch the preform 34 to the
bottom mold portion 76 and pressurized air may be directed into the
interior of the preform 34 via the compressed gas nozzle 100 at
approximately 585 PSI in order to blow mold the preform 34 into the
final container 10. The container 10 may then be demolded and
deposited onto the collection ramp 122.
[0068] In one embodiment, the preform forming station, preform
heating station 42, and blow mold station 70 may be angularly
displaced from each other by approximately 120 degrees. Thus, the
carrying apparatus 49 may be configured to rotate between the
stations at 120 degree intervals. In one embodiment, the preform 34
and/or container 10 may be present at each station for
approximately 16.8 seconds. Thus, the total cycle time for the
preform 34 to be formed, conditioned, blow molded into the final
container 10, and deposited may be approximately 50.4 seconds.
[0069] Referring now to FIGS. 10-12, an alternative exemplary blow
mold station 70' is provided. The blow mold station 70' of this
embodiment is substantially similar to that of the previous
embodiment with the primary difference being that the side mold
portion is divided into three horizontal sections 78a, 78b, 78c,
which are independently movable along the axis L via actuators and
a controller (not shown) similar to those previously described. In
this regard, the lowermost horizontal section 78a may be mounted to
the side mold platform 90 and the remaining horizontal sections
78b, 78c may be mounted to separate platforms (not shown) or
directly coupled to their respective actuators. In any event, the
horizontal sections 78a, 78b, 78c may collectively define at least
one dovetail including a tongue or a groove (not shown) extending
in a direction parallel to the axis L for forming a corresponding
dovetail on the container 10.
[0070] Thus, in the embodiment shown, the side mold portion is
divided into horizontal sections 78a, 78b, 78c arranged in a stack
along the axis L. In one embodiment, the sections 78a, 78b, 78c may
be connected together using connecting mechanisms or mechanical
fasteners (not shown), such as when in the respective molding
positions. While three such sections 78a, 78b, 78c are shown, any
suitable number may be used. For example, the number of separate
horizontal sections 78a, 78b, 78c may be selected based on the
amount of static friction which must be overcome and the number of
sections required to overcome the static friction in a manner
sufficient to avoid deforming or destroying the container 10 during
the demolding process.
[0071] In one embodiment, the controller may be configured with a
timed stroke sequence during the demolding process in which the
horizontal sections 78a, 78b, 78c of the side mold portion are
pulled down in order, from the lowermost horizontal section 78a
first to the uppermost horizontal section 78c last. For example,
each horizontal section 78a, 78b, 78c may remain static until the
next-lower horizontal section is being pulled down. In this manner,
the static upper horizontal section(s) 78b, 78c may provide support
to the container 10 for a short period of time at least until the
static friction is overcome between the lower horizontal section
78a and the container 10. Once the static friction between the
container 10 and the lower horizontal section 78a such that the
lower horizontal section 78a is moving down, as indicated by the
arrows A9 (FIG. 10), the reduced kinetic friction between the
moving horizontal section 78a and the container 10 is sufficiently
low such that the next higher horizontal section 78b can be moved
down without causing the container 10 to stretch. The upper
horizontal section 78c may assist in supporting the container 10 as
the lower horizontal sections 78a, 78b are moving down, thus
allowing the overall friction on the container 10 to be reduced by
a factor corresponding to the number of horizontal sections 78a,
78b, 78c. In the illustrated embodiment having three horizontal
sections 78a, 78b, 78c, the initial friction present between the
first moving (e.g., lowest) horizontal section 78a and the
container 10 may be only approximately one-third of the friction
that would otherwise be present between the container 10 and the
entire side mold portion 78.
[0072] Once the static friction is overcome on the lower horizontal
section(s) 78a, 78b, the remaining kinetic friction caused by the
lower moving horizontal section(s) 78a, 78b is reduced, such that
the container 10 is not deformed or destroyed by the demolding
process. One-by-one the horizontal sections 78a, 78b, 78c can be
moved down after the static friction is overcome on each, as
indicated by the arrows A10 (FIG. 11), and the remaining kinetic
friction on the horizontal sections 78a, 78b, 78c that are moving
down to release the container 10 may be insufficient to deform or
destroy the container 10. Thus, the exemplary blow mold station 70'
may prevent the container 10 from stretching and/or being pulled
apart into separate pieces during the demolding process.
[0073] In the embodiment shown, the bottom mold portion 76 is
independently movable in a manner similar to that of the previous
embodiment. Thus, the controller may be configured to pull down the
bottom mold portion 76 after the side mold portion (e.g., each of
the horizontal sections 78a, 78b, 78c) has been at least partially
pulled down in a manner similar to that of the previous embodiment,
as indicated by the arrows A11 (FIG. 12), in order to support the
container 10 during the demolding process. In another embodiment,
the controller may be configured to pull down the bottom mold
portion 76 simultaneously with one or more of the horizontal
sections 78a, 78b, 78c of the side mold portion. For example, the
controller may be configured to pull down the bottom mold portion
76 simultaneously with the lowermost horizontal section 78a of the
side mold portion. In one embodiment, the bottom mold portion 76
may be integrally formed with the lowermost horizontal section 78a
of the side mold portion as a unitary piece.
[0074] The remaining features and benefits of the blow mold station
70' are substantially similar to those of the blow mold station 70
and will be readily understood, and thus are not repeated for the
sake of brevity.
[0075] Referring now to FIGS. 13-15, an alternative exemplary blow
mold station 70'' is provided. The blow mold station 70'' of this
embodiment is substantially similar to that of the previous
embodiments with the primary difference being that the side mold
portion is divided into four vertical sections 78e, 78f, 78g (three
shown), which are independently movable in a direction parallel to
the axis L via actuators and a controller (not shown) similar to
those previously described. In this regard, each of the vertical
sections 78e, 78f, 78g may be mounted on a respective dedicated
platform 90a, 90b, 90c. At least one of the vertical sections 78e,
78f, 78g may define at least one dovetail including a tongue or a
groove (not shown) extending in a direction parallel to the axis L
for forming a corresponding dovetail on the container 10.
[0076] Thus, in the embodiment shown, the side mold portion is
divided into vertical sections 78e, 78f, 78g arranged side-to-side
about the axis L. In one embodiment, the sections 78e, 78f, 78g may
be connected together using connecting mechanisms or mechanical
fasteners (not shown), such as when in the respective molding
positions. While four such sections 78e, 78f, 78g are present in
the illustrated embodiment, any suitable number may be used. For
example, the number of separate vertical sections 78e, 78f, 78g may
be selected based on the amount of static friction which must be
overcome and the number of sections required to overcome the static
friction in a manner sufficient to avoid deforming or destroying
the container 10 during the demolding process.
[0077] In one embodiment, the controller may be configured with a
timed stroke sequence during the demolding process in which the
vertical sections 78e, 78f, 78g of the side mold portion are pulled
down in order, beginning with one or more vertical sections 78e,
78f, 78g and continuing sequentially with the remaining vertical
sections 78e, 78f, 78g. In this manner, the static vertical
sections 78e, 78f, 78g may provide support to the container 10 for
a short period of time at least until the static friction is
overcome by the moving vertical sections 78e, 78f, 78g. Once the
static friction is overcome on at least one vertical section 78e
such that the at least one vertical section 78e, 78f, 78g is moving
down, as indicated by the arrow A12 (FIG. 13), the reduced kinetic
friction between the moving vertical section 78e and the container
10 is sufficiently low such that one or more of the other vertical
sections 78f, 78g can be moved down without causing the container
10 to stretch. The static vertical sections 78e, 78f, 78g may
assist in supporting the container as the other vertical portions
78e, 78f, 78g are moving down, thus allowing the overall friction
on the container 10 to be reduced by a factor corresponding to the
number of vertical sections 78e, 78f, 78g. In the illustrated
embodiment having four vertical sections 78e, 78f, 78g, the initial
friction present between the first moving vertical section 78e and
the container 10 may be approximately one-fourth of the friction
that would otherwise be present between the container 10 and the
entire side mold portion 78.
[0078] Once the static friction is overcome on the first vertical
section 78e, the remaining kinetic friction caused by the moving
vertical section 78e is reduced such that the container 10 is not
deformed or destroyed by the demolding process. One-by-one the
vertical sections 78e, 78f, 78g can be moved down after the static
friction is overcome on each, as indicated by the arrows A13 (FIG.
14), and the remaining kinetic friction on the vertical sections
78e, 78f, 78g that are moving down to release the container may be
insufficient to deform or destroy the container 10. Thus, the
exemplary blow mold station 70'' may prevent the container 10 from
stretching and/or being pulled apart into separate pieces during
the demolding process.
[0079] In the embodiment shown, the bottom mold portion 76 is
independently movable in a manner similar to that of the previous
embodiment. Thus, the controller may be configured to pull down the
bottom mold portion 76 after the side mold portion (e.g., each of
the vertical sections 78e, 78f, 78g) has been at least partially
pulled down in a manner similar to that of the previous embodiment,
as indicated by the arrows A14 (FIG. 15), in order to support the
container 10 during the demolding process). In another embodiment,
the controller may be configured to pull down the bottom mold
portion 76 simultaneously with one or more of the vertical sections
78e, 78f, 78g of the side mold portion. In one embodiment, the
bottom mold portion 76 may be integrally formed with any of the
vertical sections 78e, 78f, 78g of the side mold portion as a
unitary piece.
[0080] The remaining features and benefits of the blow mold station
70'' are substantially similar to those of the blow mold station 70
and will be readily understood, and thus are not repeated for the
sake of brevity.
[0081] While the present invention has been illustrated by the
description of various embodiments thereof, and while the
embodiments have been described in considerable detail, it is not
intended to restrict or in any way limit the scope of the appended
claims to such detail. Thus, the various features discussed herein
may be used alone or in any combination. Additional advantages and
modifications will readily appear to those skilled in the art. The
invention in its broader aspects is therefore not limited to the
specific details and illustrative examples shown and described.
Accordingly, departures may be made from such details without
departing from the scope of the general inventive concept.
* * * * *