U.S. patent application number 11/127588 was filed with the patent office on 2006-02-02 for window covering parts and apparatus and methods for making the same.
Invention is credited to Don A. Patterson, Kendall W. Prince, Matt A. Stott.
Application Number | 20060022376 11/127588 |
Document ID | / |
Family ID | 35428747 |
Filed Date | 2006-02-02 |
United States Patent
Application |
20060022376 |
Kind Code |
A1 |
Prince; Kendall W. ; et
al. |
February 2, 2006 |
Window covering parts and apparatus and methods for making the
same
Abstract
A hollow, rigid window covering component for use as a slat or
otherwise, generally used as an alternative to wood, the component
being filled with a foam using a substantially continuous
manufacturing process. The apparatus used for this process
comprises a die having a substantially toroid-shaped resin chamber
and a channel or void through which to inject a core material into
the enclosed perimeter of the hollow window covering component.
Inventors: |
Prince; Kendall W.; (Layton,
UT) ; Stott; Matt A.; (Syracuse, UT) ;
Patterson; Don A.; (Gilbert, AZ) |
Correspondence
Address: |
KIRTON & McCONKIE;1800 Eagle Gate Tower
60 East South Temple Street
P.O. Box 45120
Salt Lake City
UT
84145-0120
US
|
Family ID: |
35428747 |
Appl. No.: |
11/127588 |
Filed: |
May 12, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60570240 |
May 12, 2004 |
|
|
|
Current U.S.
Class: |
264/140 |
Current CPC
Class: |
E06B 9/386 20130101 |
Class at
Publication: |
264/140 |
International
Class: |
D01D 5/40 20060101
D01D005/40 |
Claims
1. A method of forming a window covering component comprising the
steps of Feeding an extrudable material into a die, said die
comprising An input channel, A chamber, An exit aperture through
which said extrudable material exits said die to form a hollow
window covering component having an unbroken cross-sectional
perimeter, and Means for accessing the hollow interior of the
window covering component; Injecting a core material through said
accessing means of said die into the interior of said window
covering component in a substantially continuous process as it
exits said die.
2. A method of forming a window covering component comprising the
steps of Feeding a melted extrudable material into a die, said die
comprising An input channel into which said melted extrudable
material is fed, A chamber, said chamber comprising an inner
perimeter and an outer perimeter; and An exit aperture through
which said melted extrudable material exits said die to form the
exterior shell of said window covering component; Inserting a
delivery device into the space within said inner perimeter of said
die; Injecting a core material into the interior of said shell of
said window covering component using said delivery device; Forming
said window covering component into a desired shape; and Cooling
said window covering component.
3. The method of claim 2 in which said melted extrudable material
is selected from the group consisting of ABS, ASA, PVC,
polypropylene, polyethylene, PET, PETG, polycarbonate, polystyrene,
and composites includes any of the foregoing.
4. The method of claim 2 in which said core material is selected
from the group consisting of a thermoset plastic, a foamed
thermoplastic resin, and composites includes either of the
foregoing.
5. A window covering component comprising A shell and a core, And
formed using a process comprising the steps of Obtaining an
extrudable material; Feeding said extrudable material into a die,
said die comprising An input channel, A resin chamber, said resin
chamber comprising an inner perimeter and an outer perimeter; and
An exit aperture through which said extrudable material exits said
die to form said shell; Inserting a delivery device into the space
within said inner perimeter of said die; and Injecting a core
material through said delivery device into the interior of said
shell to form said core; and Forming said window covering component
into a desired shape.
6. The window covering component of claim 5 in which said
extrudable material is selected from the group consisting of ABS,
ASA, PVC, polypropylene, polyethylene, PET, PETG, polycarbonate,
polystyrene, and composites includes any of the foregoing.
7. The window covering component of claim 5 in which said core
material is selected from the group consisting of a thermoset
plastic, a foamed thermoplastic resin, and composites includes
either of the foregoing.
Description
RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional
application Ser. No. 60/570,240, filed May 12, 2004.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates generally to coverings for
windows or for other similar openings. More particularly, the
present invention relates to window covering parts and methods and
apparatus for making the same.
[0004] 2. Background Information
[0005] Window coverings such as shutters or blinds are often used
to cover windows and other similar openings to provide privacy or
to control the level of light that enters a room. A blind,
sometimes called a "Venetian" blind, is a popular type of window
covering and comprises a series of spaced-apart slats or louvers
assembled parallel to each other. In some cases, the slats are
disposed horizontally with respect to the window; in others, the
slats are disposed vertically.
[0006] In recent years, blinds made of wooden slats have gained
popular appeal. Since solid wood can be expensive, slats made of
various solid wood alternatives have also become popular. Examples
of such alternatives include: metal, vinyl, PVC foam, ABS wood
composite, plywood, solid thermoplastics, or a combination of any
of these. While usually less expensive than solid wood, slats
constructed from these wood-alternative materials are inferior to
solid wood slats in terms of beam strength. The inferior beam
strength, in turn, structurally limits the slat length or span
width. In other words, these wood-alternative blinds require more
support members (also called ladder supports) in order to span the
same window breadth as a wood slat. Consequently, a greater number
of ladder supports must necessarily be incorporated into
wood-alternative blinds in order to prevent the slats from sagging.
This equates to higher materials costs, higher manufacturing costs,
and a generally less aesthetically pleasing finished product.
Typically, a ladder support must be placed every 10 to 12 inches
along the length of a wood-alternative slat, compared to placing
ladder supports every 21 to 24 inches for wood slats.
SUMMARY OF THE INVENTION
[0007] In a preferred embodiment, the present invention comprises a
hollow, rigid window covering part, such as, for example, as slat,
filled with a generally less dense material, and apparatus and
methods for making the same. The apparatus comprises a die from
which hollow window covering parts are extruded. The die comprises
a void or channel which provides access to the interior of the
hollow widow covering part as it exits the die. The method
disclosed comprises adding a material to the interior of the hollow
slat through the central void or channel in the die. The resulting
combination of an extruded hollow window covering component part
filled with a second material provides a slat or other window
covering part having greater structural strength (stiffness) than
any wood-alternative material having appropriate weight and cost
characteristics, and does so via a novel and highly efficient
continuous manufacturing process.
[0008] In a preferred embodiment of the present invention, a
thermoplastic resin is extruded from the die to form the hollow
slat and a thermoset foam is introduced into the hollow slat. The
thermoset foam reacts with moisture (or with an accompanying
chemical agent) as it is introduced into the hollow slat. In
another preferred embodiment, a foamed thermoplastic resin is
introduced into the hollow slat.
[0009] Those skilled in the art will recognize that the thermoset
foam, foamed thermoplastic resin, or other suitable material
introduced into the hollow slat can easily be adjusted to different
densities so as to provide the desired balance of qualities such as
structural strength, lightness, insulating ability, materials cost,
or others.
[0010] Accordingly, it is an object of the present invention to
provide a hollow, filled window covering part designed to be
incorporated into a wood-alternative window covering.
[0011] It is another object of the present invention to provide a
strong and stiff but lightweight window covering part that is
better than any existing wood-alternative in combined strength and
lightness.
[0012] It is yet another object of the present invention to provide
an alternative material for constructing blinds and other window
coverings.
[0013] It is a further object of the present invention to provide
methods and apparatus for making window covering parts wherein a
thermoplastic resin is extruded from a die having a void or channel
in order to introduce a second material into a hollow window
covering component part.
[0014] It is a further object of the present invention to provide
sufficiently strong window covering parts comprising a smaller
volume of material than is possible using techniques in the prior
art for constructing slats and other parts from thermoplastic
resins.
[0015] It is a still further object of the present invention to
provide methods and apparatus that are capable of producing window
covering parts at an increased rate.
[0016] These and other objects and features of the present
invention will be apparent from the detailed description and by
reference to accompanying Figures.
BRIEF DESCRIPTION OF THE FIGURES
[0017] The foregoing and other objects and features of the present
invention will become more fully apparent from the following
description and appended claims, taken in conjunction with the
accompanying drawings. Understanding that these drawings depict
only typical embodiments of the invention and are, therefore, not
to be considered limiting of its scope, the invention will be
described and explained with additional specificity and detail
through the use of the accompanying drawings in which:
[0018] FIG. 1 is a cut-away cross-sectional view of a die used to
extrude a window covering component, and through which a core
material is introduced, according to a preferred embodiment of the
present invention.
[0019] FIG. 2 illustrates a front view of the die shown in FIG.
1.
[0020] FIG. 3 illustrates the steps used in a preferred embodiment
to create a window covering component according to the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The following detailed description, in conjunction with the
accompanying drawings (hereby expressly incorporated as part of
this detailed description), sets forth specific configurations in
order to provide a thorough understanding of the present invention.
The following detailed description, in conjunction with the
drawings, will enable one skilled in the relevant art to make and
use the present invention.
[0022] A purpose of this detailed description being to describe the
invention so as to enable one skilled in the art to make and use
the present invention, the following description sets forth various
specific examples, also referred to as "embodiments," of the
present invention. While the invention is described in conjunction
with specific embodiments, it will be understood, because the
embodiments are set forth for explanatory purposes only, that this
description is not intended to limit the invention to these
particular embodiments. Indeed, it is emphasized that the present
invention can be embodied or performed in a variety of ways. The
drawings and detailed description are merely representative of
particular embodiments of the present invention.
[0023] Extruding components used in the construction of window
coverings is well known in the art. Extruded components provide a
relatively low-cost, easily manufactured alternative to components
made from wood or metal. In some cases, these components are
hollow, with various shapes of ribbing or structural members
disposed within a generally hollow core. Entirely hollow structures
may lack structural strength (such as, for example, stiffness),
while the use of ribbing to increase stiffness greatly increases
the manufacturing complexity of the extrusion process. It can also
significantly increase the materials cost of the finished product,
as much more material is used to create ribbing than would be
needed to create only the shell or outer perimeter of the desired
shape.
[0024] Accordingly, it is highly desirable in the window coverings
industry to have an extruded outer shell that can be constructed
using low-cost extrusion techniques, but to introduce into the
hollow center of such components some additional material to
provide increased structural strength without greatly increasing
the weight or materials costs of the finished product.
[0025] U.S. Pat. Nos. 6,592,789 and 6,880,588, both issued to
Barsby, disclose a method of filling a hollow extruded component
with a foam. Barsby's method, however, requires that the window
covering component have an opening within its perimeter into which
a foam-injection head can be inserted as the long axis of the
extruded component passes adjacent to the injection head. Clearly,
this requirement of an open perimeter (effectively, a "U" shaped
cross-section) detracts from the desirability and flexibility of
Barsby's method.
[0026] The present invention discloses a novel apparatus and method
of introducing material into the fully-enclosed perimeter (having
an unbroken cross-section) of a hollow extruded window covering
component such as a window blind slat.
[0027] FIG. 3 illustrates the steps comprising a preferred
embodiment of the present invention. A melted resin 100 is
provided. In a preferred embodiment, a thermoplastic resin is used.
An appropriate resin may be selected by those skilled in the art
based upon the desired cost, rigidity, and other characteristics of
the finished window covering component. The resin selected may
include, but not be limited to, any of the following: ABS, ASA,
PVC, polypropylene, polyethylene, PET, PETG, polycarbonate, and
polystyrene. Various composites may be used that include any of
these or other resins. Those skilled in the art can select
materials having the desired cost, rigidity, and formability
characteristics. The melted state of the selected resin can be
achieved by any system known in the art. In a preferred embodiment,
an extrusion machine (not shown in FIG. 3) is used to melt a
pelletized thermoplastic and deliver it in a melted state as melted
resin 100 of the present invention.
[0028] Die extruder 110 comprises a die 10 having a channel 80 into
which melted resin 100 is fed using any technique known in the art.
Die 10 further comprises, in a preferred embodiment, a
substantially toroid-shaped resin chamber 40 into which the melted
resin flows as it is fed or forced into die 10. Die 10 is
represented in a cut-away cross-section in FIG. 1, and in a front
view in FIG. 2. Melted resin arrives in resin chamber 40 via
channel 80, which may be located at any point on die 10 that is
able to connect with resin chamber 40.
[0029] As additional melted resin 100 is forced into die 10, melted
resin 100 is extruded from die 10 at exit aperture 50. Noting the
generally toroid shape of resin chamber 40, the resulting extruded
material 60 is, in a preferred embodiment, in the form of a
cylinder. It will be appreciated, however, that other extruded
shapes could easily be created at this point by manufacturing die
10 with a different exit aperture 50, and forming resin chamber 40
in an appropriate shape that includes other key features as herein
disclosed.
[0030] The hollow extruded component 60 may be formed as a unitary,
extruded member as described and illustrated above. Alternatively,
component 60 could be formed as two or more separate elements that
are then combined by means of an adhesive or otherwise to form a
hollow component having a substantially continuous, fully-enclosed
perimeter.
[0031] The substantially toroid shape of resin chamber 40 permits a
hollow channel or void 20 to be manufactured as part of die 10, so
that surface 12 forms the inner portion of exit aperture 50 of die
10, but permits access to the hollow portion of extruded material
60.
[0032] In a preferred embodiment, a mandrel 30 is inserted into
void 20. Mandrel 30 is connected to a delivery device (not shown)
capable of delivering a core material 70 into the center of
extruded material 60. Alternatively, die 10 could simply include a
suitable channel that communicates with the hollow interior of
extruded material 60 though which core material 70 may be
delivered.
[0033] In a preferred embodiment, core material 70 comprises a
thermoset foam such as polyurethane. Numerous other thermoset
foams, foamed thermoplastic resins, or other suitable foam core
materials are encompassed within the scope of the present
invention. The core material, in a preferred embodiment, is
delivered in a liquid state, and immediately reacts with moisture
or an associated chemical curing agent to begin curing into a solid
foam. The state of melted resin 100 as it exits die 10 at exit
aperture 50 is such that core material 70 does not necessarily
react chemically with melted resin 100, but merely fills the hollow
space within the extruded material 60.
[0034] Referring again to FIGS. 1 and 3, extruded material 60, now
filled with core material 70, is fed into calibrator 130 after
leaving die extruder 110. Calibrator 130 includes an appropriate
mold that forms extruded material 60 into the final shape desired
for the finished window covering component. Because extruded
material 60 is not fully cooled, and core material 70 is not fully
cured, upon entering calibrator 130, the shape of extruded material
60 can be formed by the molds within calibrator 130. Any shape
required for a window covering component may be formed in
calibrator 130, including, without limitation, cross-sectional
shapes such as ovals, airfoils, rectangles, and circles.
[0035] Importantly, calibrator 130 is constructed so as to exert a
vacuum pressure on the extruded material 60, and to cool it in a
controlled manner using a water bath, air cooling, or any other
cooling technique known in the art. The combination of vacuum
pressure exerted by calibrator 130 and the internal pressure caused
by the curing of core material 70 ensures that extruded material 60
presses firmly against the mold within calibrator 130, maintaining
a fixed and regular shape as it passes through calibrator 130 until
it is sufficiently cooled and cured. In a preferred embodiment
using a thermoplastic resin as extruded material 60 and
polyurethane foam as core material 70, the forming and cooling
process is completed after about five feet of traverse within
calibrator 130.
[0036] Those skilled in the art will recognize the inherent
advantages of the present invention compared to prior art
techniques involving insertion of a foam-like piece into a
pre-formed, cooled, and cut hollow window coverings component. The
prior art techniques are non-continuous, cannot provide significant
structural enhancements, and provide relatively little flexibility
in the nature of the core material used without additional
materials costs or retooling. The present invention provides the
advantages of being a continuous manufacturing process, providing,
at the user's option, significant enhancement to structural
rigidity, and being a flexible process that permits on-the-fly
adjustments of core material density without changing materials or
tooling.
[0037] Those skilled in the art will also appreciate that the
nature of core material 70 can be adjusted as needed at the
beginning of a manufacturing process, or during a manufacturing
process, to achieve the desired characteristics in the finished
product. As specific non-limiting examples, if a lightweight
product is desired, the density of foam used for core material 70
can be changed by adjusting the ratios of liquid components (resin
and hardener) used in a thermosetting foam, or by adjusting the
nature or degree of the blowing agent used with a thermoplastic
resin that is used as core material 70. Likewise, if one skilled in
the art desires that core material 70 provide additional structural
strength, similar adjustments can be made to increase the density
of core material 70. In this manner, the amount of materials used
to construct a given length of a window covering component can very
easily be adjusted to suit the cost and market needs of the
manufacturer. Indeed, if structural strength (stiffness) is
selected as a primary goal for the manufacturing process, the
present invention provides the ability to manufacture a window
covering slat having greater stiffness compared to its weight than
any other wood-alternative presently available.
[0038] Once fully formed and cooled within calibrator 130, extruded
material 60, filled with core material 70, exits calibrator 130 as
finished product 140. Finished product 140 can then be cut to a
desired length, a decorative element can be added, or it can be
further processed as desired. Decorations may be added to a
finished product by means of coloring, painting, embossing,
staining, foiling, printing, wrapping, coating, or by any other
means known in the art.
[0039] It is underscored that the present invention may be embodied
in other specific forms without departing from its spirit or
essential characteristics. The embodiments described herein should
therefore be deemed only as illustrative.
* * * * *