Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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HENDAHLE FOAM COVERED ROD-LIKE ARTICLE
AND METHOD AND APPARATUS FOR MAKING SAME
BACKGROUND OF THE INVENTION
Field of the Invention
The invention generally relates to foam
covered bendable rod-like articles and associated
methods and apparatus. More specifically, the
invention relates to bendable closed cell foam covered
rod-like articles having specially constructed end
portions.
Description of the Prior Art
Foam covered bendable wire products are
commonly utilized in a variety of fields. For example,
such devices are often used as hair curlers, holders
for ponytails, and the like. Examples of such devices
are described in U.S. Patent No. 2,542,601 to Van Cleef
and U.S. Patent No. 4,577,647 to Fenster, et al. One
problem typically encountered with such articles is
that the wire core has a tendency to shift within the
~ foam sheath; thus, the Van Cleef and Fenster, et al.
patents describe structures designed to eliminate
relative movement between the wire core and foam
sheath. The van Cleef patent describes a hair curler
having a wire core with looped ends and a rubber sheath
having knobbed ends for containing the looped ends of
the wire core, in order to reduce the tendency of the
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wire core to shift within the rubber sheath. Trre--
Fenster, et al. patent seeks to overcome the problem of
relative movement between a wire core and foam sheath
by providing anchoring means on the core to assist in
the core and sheath adjoinment; the anchoring means is
described as being either bristle-type members
extending from the core or a primer which reacts with
the foam material. While such devices represent an
improvement over prior art methods, the curlers
generally must be manufactured one-at-a-time (and thus
are relatively expensive to produce), and relative
movement between the core and sheath components tends
to occur after the article has been used (i.e., bent
and straightened) a number of times.
Foam covered wire products have also in
recent times become popular as novelty items, such as
novelty jewelry, toys and the like. Such novelty
articles are typically produced according to one of two
methods. In the first method, a version of which is
described in U.S. Patent No. 5,498,190 to Ganson, a
hollow foam tube is produced to have an opening which
approximates the size of a wire core which is to be
inserted. A wire core is cut to a length which is
somewhat shorter than the length of the hollow foam
tube, and the ends of the wire core are usually rounded
in a conventional manner to eliminate their sharpness.
The core is coated with an RF activated adhesive, and
the thus-coated wire core is inserted into the hollow
foam tube (usually manually) such that the wire core is
centered along the foam tube length. As a result, the
wire core ends are recessed within the respective
corresponding ends of the foam tube. The adhesive is
then activated to secure the wire core to the foam
tube. The ends of the foam tube can then be treated
and a brand applied to the end face of the foam tube to
enclose the wire core. While the resulting product has
the safety advantages of a recessed wire core which
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optionally has dull ends, it is often difficult-to get
a good bond between the wire core and foam tube. As a
result, the wire core has a tendency to separate from
the foam tube (particularly following the repeated
bending and straightening which the article undergoes
during use) and it can slide out, thus destroying the
product's utility. In addition, the assembly process
requires matching predetermined lengths of foam tube
with slightly shorter predetermined lengths of wire,
inserting and centering the wire in the foam tube, and
then bonding the wire to the tube. These assembly
steps are laborious and expensive, and cause assembly
time to be great.
The second known prior art method of
producing such articles is described in U.S. Patent No.
4,648,414 to Fox, et al. The Fox, et al. patent
describes an article having a pliable wire core and a
closed cell foam sheath surrounding the core. The
article is made by coating the wire core with an
adhesive and feeding the coated wire core to an
extrusion die, where a foam sheath is extruded about
the core. The thus-coated core is then cut into rods
of predetermined length, and hot thermoplastic end caps
are bonded to the opposite ends of each of the rods.
In the resulting article, the foam sheath and the wire
core are coextensive in length, with the end caps
serving to seal the rod ends and prevent liquid from
coming into contact with the wire core. Further, the
patent describes that the adhesive serves as a
corrosion resistant protective coating for the wire
core, as well as securing the wire core to the foam
sheath.
While the article and the method of the Fox,
et al. patent have been found to be useful in many
respects (i.e., an excellent bond is obtained between
the core and sheath and the cost of production is
relatively lower than that of the first method
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described above), the wire core extends to the ends of the foam sheath and the
ends of the wire core are squared-off rather than being rounded. The end caps
are thus advantageously used to shield a user from exposure to the squared off
ends of the wire core. However, the end caps add to the manufacturing cost
and, once in use, can separate from the article, thereby exposing a user to
the
wire core and the ends of the wire core to adverse influences such as
moisture.
SUMMARY OF THE INVENTION
With the foregoing in mind, it is therefore an object of the present
invention to provide a closed cell foam-covered bendable rod-like article
which
can be manufactured inexpensively and requires only a minimal number of
production steps.
It is also an object of the invention to provide a method for forming a
foam covered rod-like article where the ends of the core are safely retained
within the foam such that they cannot injure a wearer or user.
It is a further object of the invention to provide a method for making a
foam-covered bendable rod-like composite article which resists separation of
the foam and the core, even following repeated bending and straightening of
the
article.
In addition, it is an object of the present invention to provide a closed cell
foam-covered bendable rod-like article in which the core ends are safely
encapsulated and which retains a strong bond between the flexible core and
foam sheath throughout a number of bendings and straightenings.
According to an object of an aspect of the present invention, there is
provided a method for making a bendable, rod-like article having a flexible
core
and a foam sheath comprising the steps of:
advancing a continuous flexible core along a predetermined path
of travel;
applying an adhesive coating to the flexible core;
feeding the thus-coated core to an extruder;
extruding a foam sheath about the core with the extruder to form
a composite structure defining a central axis;
cutting the composite structure to form predetermined lengths of
discrete rod-like elements each having opposed ends defined by the axially
coextensive ends of the core and sheath;
securing each respective rod-like element in a fixed position;
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pressing an orificed plate and one of the ends of
the foam sheath of the rod-like element against each other in
an axial direction such that the respective end of the foam
sheath is compressed and the corresponding end of the core
extends through the orifice of the plate;
cutting and removing the portion of the core end
extending through the plate orifice;
releasing the pressure between the plate and the
foam sheath such that the sheath decompresses to extend beyond
the core end;
smoothing each of the ends of the core such that
each end has a diameter which is not substantially greater than
a central portion of the flexible core;
pressing an orificed plate and the other of the ends
of the foam sheath of the rod-like element against each other
in an axial direction such that the respective end of the foam
sheath is compressed and the corresponding end of the core
extends through the orifice of the plate;
cutting and removing the portion of the core end
extending through the plate orifice;
releasing the pressure between the plate and the
foam sheath such that the sheath decompresses to extend beyond
the core end; and
sealing each of the ends of the foam sheath to
enclose the core ends within the foam sheath.
According to another object of an aspect of the
invention, there is provided a method for making a bendable,
rod-like article having a flexible core and a foam sheath
comprising the steps of:
providing a continuous composite structure including
a foam sheath extruded about a flexible core and defining a
central axis;
cutting the composite structure to form
predetermined lengths of discrete rod-like elements each having
opposed ends;
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positioning an orificed plate against one of the ends of said
element such that the plate orifice is axially aligned with
said core;
compressing the orificed plate against the end of
the foam sheath of the composite structure such that a
corresponding end of the core extends through the plate
orifice;
cutting and removing a portion of the core end
extending through the plate orifice, to thereby shorten the
length of the core; and
releasing the compression of the plate against the
foam sheath such that the sheath returns substantially to its
original orientation and the core end is recessed within the
foam sheath, and smoothing each of the ends of the core such
that each end has a diameter which is not substantially greater
than a central portion of the flexible core.
According to a further aspect of the present
invention, there is provided a method of finishing the ends of
a foam-coated bendable rod-like article comprising the steps
of
pressing an orificed plate and an end of a closed
cell foam-coated flexible core together such that a portion of
the end of the core extends through the orifice of the plate;
cutting and removing the portion of the core
extending through the orifice and moving at least one of the
plate and the core in an opposed direction to the other such
that the foam decompresses to extend beyond the core end, and
smoothing each of the ends of the core such that each end has a
diameter which is not substantially greater than a central
portion of the flexible core.
According to yet a further aspect of the present
invention, there is provided an apparatus for finishing an end
of a bendable rod-like element having a flexible core and an
axially coextensive foam sheath, said apparatus comprising:
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a vise positioned adjacent to the end of the rod-
like element for fixedly supporting the end thereof;
a compressive member defining an orifice in axial alignment
with the core and having an engagement surface surrounding said
orifice for engaging the end of the foam sheath of the element,
said compressive member being movable relative to said vise for
causing the end of the core to extend through said orifice and
the engagement surface to compress the corresponding portion of
the foam sheath in an axial direction; and
a blade adjacent said compressive member for cutting
and removing the portion of core extending beyond said
compressive member, and a device for smoothing the end of the
core to a diameter that is not substantially greater than a
central portion of the flexible core.
According to another aspect of the present
invention, there is provided a bendable foam-covered article
comprising:
a flexible core having a predetermined length and
opposing ends, the ends being smooth and having a diameter that
is not substantially greater than a central portion of the
flexible core;
an adhesive coating bonded to said core, and
a low density, closed cell foam sheath extruded against
the adhesive-coated core such that the adhesive coating is
structurally integrated with a radially inner portion of said
sheath, said sheath defining a second predetermined length
which is greater than said predetermined length of said
flexible core such that said opposing ends of the core are
recessed within the foam sheath.
These and other objects are met by the method,
article, and apparatus of the instant invention as follows.
A flexible core is advanced from a supply source through an
adhesive coating apparatus which
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applies an adhesive coating to the flexible core-.--- In a
preferred form of the invention, the adhesive coating
is applied so as to continuously surround the flexible
core. The thus-coated core is then fed through an
- 5 extrusion die where a low density closed cell foam
sheath is extruded about the core and bonded thereto by
way of the adhesive. Thus, a continuous foam-covered
flexible composite is produced.
The thus-produced covered core is then cut to
produce a plurality of rod-like elements of
predetermined length. To finish its ends, the element
is secured in a fixed position, such as by clamping it
within the jaws of a vise at a position on the rod-like
element spaced inwardly from the end to be finished.
A plate having an orifice which is
substantially the same size and dimension as the
diameter of the flexible core plus the adhesive coating
is aligned against the element such that the orifice is
longitudinally aligned with the core. One of or both
of the element and the plate is moved relative to the
other such that the foam sheath is compressed while the
core extends outwardly through the plate orifice. The
portion of the core extending outwardly from the plate
is then cut and removed, and the pressure of the plate
against the covered core is then released such that the
foam returns to substantially its original,
decompressed condition by way of its inherent recovery
properties. Alternatively, the end of the core
extending through the plate orifice can be ground,
rounded, or otherwise shaped (as opposed to cut and
removed) to smooth and/or shorten the core end.
The process is likewise performed on the
other element end. As a result, the core is shorter
than the foam sheath such that the flexible core ends
are recessed within the foam sheath. In a preferred
form of the invention, the ends of the core are also
smoothed at this time by way of an orbital riveting
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head or the like. Alternatively, the portion of--the
flexible core extending through the plate can be cut at
a position spaced from the plate and the remaining
portion can be smoothed in a conventional manner to
remove sharp edges. The ends of the element are then
sealed to enclose the ends of the flexible core,
preferably by contacting the sheath ends with a torch
or hot brand.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of an end
portion of a foam covered core according to the instant
invention, prior to the end shaping and sealing steps
of the method;
Fig. 2 is a cross-sectional view of the foam
covered core of Fig. 1, as it appears when clamped
within a vise and with an orificed plate and a cutting
member positioned proximate the end of the foam covered
core such that the core is longitudinally aligned with
the plate orifice;
Fig. 3 is a cross-sectional view of the foam
covered core and apparatus from Fig. 2, as they appear
following compression of the foam sheath by the
orificed plate;
Fig. 4 is a cross-sectional view of the foam
covered core and apparatus from Fig. 3, illustrating
the cutting and removing of the portion of the core
which extends through the plate orifice following
compression of the foam sheath;
Fig. 5 is a cross-sectional view of the foam-
covered core and apparatus from Fig. 4, illustrating
the foam covered core as it appears when the
compression of the plate is released, with the foam
sheath assuming its pre-compression position;
Fig. 6 is a cross-sectional view of the foam
covered core from Fig. 5 as it appears when the core
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end is being rounded by way of an orbital riveting--
head;
Fig. 7 is a cross-sectional view of the foam
covered core from Fig. 6, as it appears when the end is
being sealed by a hot brand apparatus; and
Fig. 8 is a perspective view of an end
portion of a finished article, with the flexible core
illustrated in phantom lines.
DETAILED DESCRIPTION OF THE INVENTION
The present invention now will be described
more fully hereinafter with reference to the
accompanying drawings, in which preferred embodiments
of the invention are shown. This invention may,
however, be embodied in many different forms and should
not be construed as limited to the embodiments set
forth herein; rather, these embodiments are provided so
that this disclosure will be thorough and complete, and
will fully convey the scope of the invention to those
skilled in the art. Like numbers refer to like
elements throughout.
With reference to the drawings, the method of
the instant invention is performed as follows. A
flexible core 10 is advanced from a supply source
through an adhesive coating apparatus which applies an
adhesive coating 12 to the core, in a manner like that
described in the above-referenced U.S. Patent No.
4,648,414 to Fox, et al.
Although the core is illustrated as being a
cylindrically shaped monofilament type core, it is
noted that cores having a non-cylindrical cross-
section, and those formed of more than a single core
strand, can also be used within the scope of the
present invention. Similarly, the core can be of any
desired diameter and flexibility. Particularly
preferred for use as a core, and especially when the
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article is designed to be used as a children's toy, is
a core material which is relatively easy to bend, yet
is sufficiently rigid that it retains the finished
article in a position in which it is contorted until
sufficient force is applied to bend the article into a
new position. In other words, in many embodiments of
the invention, it is desirable to use a core which can
be posed, and which retains its position until it is
re-posed. In other embodiments of the instant
invention, it is desirable to use a flexible core which
can be bent, but which has a tendency to regain its
original configuration without the application of
additional force; in other words, the core has a
tendency to spring back to its original configuration
after the posing force is removed, either rapidly or
over a period of time.
In a preferred form of the invention, the
adhesive coating 12 is applied so as to continuously
surround the core 10. The flexible core 10 is
desirably formed from a core material such as soft
aluminum, stainless steel, copper or the like, or a
non-metallic but flexible material such as fiberglass
(e. g., metallic cores are generally used in the posable
embodiments of the invention, while fiberglass is
generally used as the core in the article which is
designed to spring back to its original configuration
without the application of force.)
The adhesive preferably includes or consists
substantially entirely of ethylene acrylic acid
copolymer (EAA), ethylene methacrylic acid, ethylene
ethyl acrylate, or ethylene vinyl acetate. One EAA
found to be useful in the method of the instant
invention is manufactured by Dow Chemical Co. under its
product number Dow EAA 455. The adhesive is desirably
formed as a coating having a thickness equal to about
one-tenth to one-seventh the diameter of the core being
used; however, as will be readily appreciated by those
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of ordinary skill in the art, other ratios of adhesive
thicknesses can be used, provided the adhesive is
capable of securing a foam sheath to a core in the
manner discussed below.
The adhesive-coated core 10 is then fed
through an extrusion die where a foam sheath 14 is
extruded about the core and bonded thereto by way of
the adhesive. Thus, a continuous strand of foam
covered flexible core composite is produced.
Particularly preferred for the sheath is a low density,
closed cell foam material. Although the sheath is
illustrated as being substantially cylindrical, it is
to be noted that the sheath can be in a non-cylindrical
form within the scope of the present invention. The
foam sheath also desirably completely surrounds the
core, and can be of any desired diameter and
proportional diameter to the core, depending on factors
such as the anticipated end use of the article being
produced, strength and flexibility of the core being
covered, and the like. For example, where the article
is intended to be used as novelty jewelry, it is
generally preferred that the overall article have a
diameter of about one inch or less. The article could
also be used as a tie member for tying other articles
together, and thus the diameter of the foam would be
dependent on the amount of cushioning desired for the
tied articles. Likewise, where the article is intended
for use as a swimming pool toy, article diameters of at
least about three inches are generally preferred.
Furthermore, a single sheath can be extruded about more
than one spaced apart core to produce band-shaped
composite articles or to provide additional rigidity to
the finished article.
Although the method of extruding the foam
material to an adhesive-coated flexible core has been
discussed above as being performed in a manner like
that described in the Fox, et al. patent, is to be
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noted that the method and article of the instant---
invention can be performed using other types of foams,
cores and adhesives as well as adhesive and extruding
methods, such as those commonly known for forming other
types of foam-covered flexible cores (e. g., those used
in the formation of coaxial cables.) Two patents
describing such processes are U.S. Patent No. 4,104,481
to Wilkenloh, et al., and U.S. Patent No. 4,107,354,
also to Wilkenloh, et al. It is particularly
preferred to use an adhesive and extrusion process
which tends to result in the structural integration of
the adhesive within a radial inner portion of the foam
sheath, as this has been found to provide particularly
durable securement of the core and sheath; for example,
an EAA adhesive which reacts at elevated temperatures
such as those provided by the foam material during the
extrusion of the foam sheath can be used to achieve a
strong bond between the core and sheath. The extrusion
of the foam directly to the adhesive-covered core
provides a much stronger and more durable bond than the
above-mentioned RF activated adhesive method where a
foam tube has been fully formed and cooled before the
core is adhered thereto.
In a preferred form of the invention, the
closed cell foam sheath has a specific gravity of about
0.05 to 0.15 grams/cc, and more preferably a specific
gravity of about 0.10 to 0.15 grams/cc. A conventional
resin found to be useful in forming the closed cell
foam is a polyethylene resin having a melt index_ of 2.0
and a density of 0.92 grams/cc. A blowing agent,
nucleator, and/or color pigment can also be added to
the polyethylene resin to provide the desired foam
characteristics and colcr ir~ a conventional manner;
e.g., based on the weight of the polyethylene resin, 5%
of a blowing agent, 1% talc can be used as a nucleator,
and 1/2 oz. colox pigment can be added to achieve a
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colored foam product. Other closed cell foam ---
compositions (e.g., polyolefin) can be used within the
scope of the invention, with the type of foam used
being selected to provide the desired rigidity,
compressiveness, buoyancy, and the like.
The foam sheath 14 is also desirably farmed
with an integral liquid impervious skin-like outer
surface 15 by the extrusion process in a known manner.
The skin-like surface 15 can serve to resist absorption
of liquids into the foam sheath, such as hair solutions
which could shorten the life of the foam, or water,
which could reduce the buoyancy of the article such as
when the article is used as a swimming pool toy. The
skin-like outer surface is preferably also provided
with a pebbled surface in a conventional manner (such
as by coalescence of collapsed foam bubbles on the foam
sheath surface), with the pebbled surface serving to
increase the frictional resistance of the outer surface
of the article to facilitate easy finishing of the
article and gripping of the finished article.
The thus-produced covered core is then cut to
produce a plurality of rod-like elements 16 of
predetermined length, an example of which is
illustrated in Fig. 1. Although shown as being cut
substantially perpendicularly to the longitudinal axis
of the foam covered core 10, it is noted that other
cutting angles or configurations could be used within
the scope of the present invention. This cutting can
be performed with any conventional apparatus, such as a
knife, wire cutter, or the like. Further, the rod-like
elements can be of various lengths as well as
diameters, depending on the end use for which the
article is designed. For example, where the article is
to be used as a hair curler, it would desirably be
about three to six inches in length, or if the article
is designed to be used as a pool toy, it can be up to a
number of feet in length (e. g., two to six feet.)
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_ As shown in Fig. 2, one of said rod-like-
elements 16 is then secured in a fixed position. In a
preferred form of the invention, the element 16 is
secured by clamping it within a vise 18 at a position
on the element spaced from the end thereof. A plate 20
having an orifice 22 which is substantially the size of
the core 10 of the element is aligned against the end
of the element such that the core is longitudinally
aligned with the orifice in the plate. In a preferred
form of the invention, the orifice 22 is tapered or
graduated from a relatively wider mouth 22a proximate
the vise 18, to a relatively narrower mouth 22b on the
other plate side, remote from the vise. In this way,
the alignment and feeding of the core 10 through the
orifice 22 is aided. In this embodiment, however, it
is desirable for each of the relatively wider and
narrower mouths to be at least as large as the core
which is to be received through the orifice in the
manner discussed below.
One or both of the element 16 and the plate
20 are then advanced toward each other so that the foam
sheath 14 is compressed while the core 10 extends
outwardly through the orifice 22 of the plate 20. In
the illustrated method of the invention, the rod-like
element 16 remains fixed while the plate 20 is advanced
toward it; alternatively, the plate can remain fixed
while the vise 18 is advanced toward the fixed plate.
As a further alternative, both the plate 20 and the
element 16 can be advanced toward each other. In
addition, it is not necessary that the element 16
remain relatively stationary, and it is within the
scope of the invention that both the plate 20 and
element 16 are moved in the same direction, but at
slightly different speeds to effect the compressing
action, in the nature of an "in-line" process.
Fig. 3 illustrates the extension of the core
10 through the orifice 22 as the bond between the foam
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sheath 14 and core is broken. A portion of the foam
sheath 14 is stripped away from the core 10 as the
portion of the core extends through the orifice 22.
In a preferred form of the invention which is
illustrated in Fig. 4, the portion of the core 10
extending outwardly from the plate orifice 22 is then
cut and removed using a conventional cutting member
such as a knife, wire cutter, or the like. In a
particularly preferred form of the invention, a knife
24 abuts the orificed plate 20 and slides directly
along the plate when cutting the core 10, such that
substantially the entire portion of the core which
extends through the orificed plate is cut and removed.
The pressure of the plate 20 against the covered core
is released such that the foam sheath 14 returns to its
original position by way of its inherent recovery
properties. (See e.g., Fig. 5.) As a result, the core
10 has a shorter length than the foam sheath 14 in its
decompressed state, such that the core end is recessed
within the foam sheath, and a recessed channel 26
between the core end and the foam sheath end is
defined.
In a preferred form of the invention, the end
of the core 10 is smoothed at this time, in order to
remove any sharp edges thereon and to otherwise blunt
the end left by the cutting step. This increases the
safety of the finished article by eliminating sharp
edges, and can increase the lifespan of the finished
article because a dull-ended core has less of a
tendency to damage the foam sheath than a sharp-ended
one. In a preferred form of the invention, this
smoothing of the core end is performed by way of an
orbital riveting head 28 or the like, such as that
shown in Fig. 6. The orbital riveting head 28 has a
cup-shaped bit which is rotatable about its axis and
orbitally turned by way of a motor, to round off any
sharp edges which may be present as a result of the
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cutting of the core. In this illustrated version-of
the invention, the orbital riveting head 28 is
elongate, and is sized to extend into the recess
channel 26 within the foam sheath 14. It is to be
noted, however, that the cut end of the core 10 could
also be smoothed using grinding. or other techniques.
Alternatively, after the core 10 is cut (and
particularly when it is cut immediately adjacent the
plate 20), the foam sheath 14 can be compressed further
such that an additional portion of the core extends
through the orificed plate; this portion of the end can
then be smoothed in the manner discussed above prior to
the release of the pressure between the plate and the
foam sheath. In this method, the cutting member 24 is
desirably either moved out of the path of the plate
orifice 22, or the cutting member contains an opening
which is adapted to align with the plate orifice, so
that the core can extend through both the orificed
plate 20 and the cutting member during the smoothing
process.
In an alternative method of the invention,
the core 10 can be clipped at a position spaced
slightly from the orificed plate 20, and the end of the
core left extending from the plate orifice can be
rounded prior to the separation of the plate 20 and
element 16, and decompression of the foam sheath 14.
As a further alternative, the core 10 end can be
ground, rounded, or otherwise shaped (as opposed to cut
and removed) to smooth and/or shorten the core end.
The ends of the article are then sealed in
order that the core 10 is enclosed, and preferably
entirely surrounded, by the material of the foam sheath
14. The sealing can be done in a conventional manner,
such as by contacting the foam sheath ends with a torch
or hot brand 30, which at least partially melts the
sheath ends so that they encapsulate the core 10. In
the sealing method illustrated in Fig. 7, the end of
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the element to be finished is forced into a conical
end-shaping device 32, which compresses the foam sheath
material together over the end of the core 10. The end
of the conical end-shaping device is left open, and a
hot brand 30 is inserted into the open end to partially
melt and seal the end of the element 16 to encapsulate
the core 10. Although described as being conical, it
is to be noted that any shape or device for compressing
the foam sheath can be used within the scope of the
instant invention. By using the material of the foam
sheath 14 to seal the ends of the element, the need for
thermoplastic end caps such as those described in the
Fox, et al. patent can be obviated. The finishing
process is likewise performed on the other end of the
rod-like element, either simultaneously with or
subsequent to the finishing of the first end.
The above-described method thus can rapidly
produce a number of foam-covered rod-like articles 16
(as shown in Fig. 8) using only a minimal number of
production steps. The thus-produced article has
enhanced safety over prior art structures due to the
rounded core ends, the core being recessed within the
foam sheath, and the complete encapsulation of the core
by the foam sheath. Furthermore, because the foam
sheath is extruded to the flexible core (as opposed to
being produced as separate subsequently joined
elements), the foam sheath can closely surround the
core, and the extra space which is required in the
prior art foam tube and wire core assembled devices is
neither needed nor produced. In addition, it has been
found that the adhesive which is coated on the core
becomes integrated into a radially inner portion of the
foam sheath during the extrusion process, thereby
providing a durable and strong securement of the core
and sheath.
Many modifications and other embodiments of
the invention will come to mind to one skilled in the
CA 02258497 1998-12-16
WO 98/47402 PCT/US97/06733
-16-
art to which this invention pertains having the benefit
of the teachings presented in the foregoing
descriptions and the associated drawings. Therefore,
it is to be understood that the invention is not to be
limited to the specific embodiments disclosed and that
modifications and other embodiments are intended to be
included within the scope of the appended claims.
Although specific terms are employed herein, they are
used in a generic and descriptive sense only and not
for purposes of limitation.
