U.S. patent application number 11/268421 was filed with the patent office on 2006-03-09 for securing electrical conductors.
This patent application is currently assigned to Velcro Industries, B.V., a Netherlands Antilles corporation. Invention is credited to Mark A. Clarner, John Demain, Christopher M. Gallant, Michel Labrecque.
Application Number | 20060049545 11/268421 |
Document ID | / |
Family ID | 27399653 |
Filed Date | 2006-03-09 |
United States Patent
Application |
20060049545 |
Kind Code |
A1 |
Gallant; Christopher M. ; et
al. |
March 9, 2006 |
Securing electrical conductors
Abstract
An elongated electrical cable or flexible circuit board includes
an electrically conductive path and an insulating body encompassing
and electrically isolating the conductive path, the insulating body
including an exposed surface having an array of fastener elements
extending therefrom, the fastener elements arranged and constructed
to engage mating fastener elements associated with a supporting
surface to selectively secure the cable or flexible circuit board
to the supporting surface. The fastener elements can be
loop-engageable fasteners and/or loops. Such a cable or flexible
circuit board is continuously formed by introducing an electrical
insulating material including a thermoplastic resin into a gap
formed adjacent a peripheral surface of a rotating mold roll, the
mold roll defining an array of cavities therein, the insulating
material being introduced under pressure and temperature conditions
selected to cause the insulating material to at least partially
fill the cavities to form fastener element stems integrally with
and extending from one broad side of a strip of said insulation
material; while introducing conductive wires and/or a conductive
path formed on or within a substrate to the gap so as to cause the
insulating material to envelop and electrically isolate the
conductive path and/or to cause the conductive path to become an
integral part of the strip of insulation material from which the
fastener element stems extend.
Inventors: |
Gallant; Christopher M.;
(Nottingham, NH) ; Labrecque; Michel; (Manchester,
NH) ; Clarner; Mark A.; (Concord, NH) ;
Demain; John; (Olney, GB) |
Correspondence
Address: |
FISH & RICHARDSON PC
P.O. BOX 1022
MINNEAPOLIS
MN
55440-1022
US
|
Assignee: |
Velcro Industries, B.V., a
Netherlands Antilles corporation
|
Family ID: |
27399653 |
Appl. No.: |
11/268421 |
Filed: |
November 7, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10423816 |
Apr 25, 2003 |
6977055 |
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11268421 |
Nov 7, 2005 |
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PCT/US01/46045 |
Oct 25, 2001 |
|
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|
10423816 |
Apr 25, 2003 |
|
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60243353 |
Oct 25, 2000 |
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60293743 |
May 25, 2001 |
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60323244 |
Sep 19, 2001 |
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Current U.S.
Class: |
264/272.11 ;
264/167; 264/277; 264/279.1 |
Current CPC
Class: |
B29C 43/222 20130101;
H01B 7/40 20130101; B29C 43/28 20130101; H05K 2203/1545 20130101;
H05K 2201/209 20130101; H05K 3/202 20130101; H05K 1/0393 20130101;
H05K 3/0058 20130101; B60R 16/0207 20130101; H05K 3/326 20130101;
H05K 2201/09118 20130101; Y10T 428/2933 20150115; H01B 7/08
20130101; B29L 2031/729 20130101; H05K 2203/0143 20130101; B60R
16/0215 20130101; B29C 2043/465 20130101; H05K 3/365 20130101; H05K
3/0014 20130101; H05K 2203/0113 20130101 |
Class at
Publication: |
264/272.11 ;
264/279.1; 264/167; 264/277 |
International
Class: |
A63B 37/00 20060101
A63B037/00 |
Claims
1-67. (canceled)
68. A method of forming an electrical cable, the method comprising:
introducing a plurality of longitudinally extending electrical
conductors into a gap defined adjacent a pressure roll; and
introducing moldable resin into the gap under conditions that cause
the resin to encapsulate the electrical conductors; wherein the
pressure roll defines a plurality of recesses and the electrical
conductors are substantially aligned with the recesses.
69. The method of claim 68 wherein the gap is a nip defined between
a mold roll and counter-rotating pressure roll.
70. The method of claim 69 further comprising solidifying the resin
on a peripheral surface of the mold roll and stripping the
solidified resin and encapsulated electrical conductors from the
mold roll.
71. The method of claim 69 further comprising molding fastener
stems integrally molded with and extending from a resin base.
72. The method of claim 71 wherein molding fastener stems
comprising molding fastener stems with integrally molded loop
engageable heads.
73. The method of claim 68 wherein the recesses are substantially
circumferentially extending grooves.
74. The method of claim 73 wherein the grooves extend around a
diameter of the pressure roll.
75. The method of claim 68 further comprising introducing the resin
and encapsulated electrical conductors into a nip defined between a
second pressure roll and a mold roll; and molding fastener stems on
the resin encapsulating the electrical conductors.
76. The method of claim 68 further comprising guiding the
electrical conductors into alignment with the grooves using a guide
plate.
77. The method of claim 68 wherein each groove is sized to receive
the aligned conductors.
78. The method of claim 68 wherein the conductors comprise
wire.
79. The method of claim 68 wherein introducing the moldable resin
into the nip comprises introducing the moldable resin into the nip
such that the resin separates adjacent electrical conductors.
80. The method of claim 68 further comprising controlling the
lateral position of the electrical conductors by introducing a
supporting substrate into the nip between the electrical conductors
and the pressure roll.
81. The method of claim 80 wherein the supporting substrate spaces
the electrical conductors from the pressure while allowing the
resin to fill the grooves.
82. A method of forming an electrical cable, the method comprising:
introducing a plurality of longitudinally extending electrical
conductors into a nip defined between a mold roll and a pressure
roll; introducing moldable resin into the nip under conditions
causing the resin to enter mold cavities defined in the peripheral
surface of the mold roll; and attaching the electrical conductors
to the resin; wherein the electrical conductors have sufficient
flexibility to conform to a peripheral surface of the mold roll,
the pressure roll defines a plurality of substantially
circumferentially extending grooves, and the electrical conductors
are introduced into the nip substantially aligned with the
grooves.
83. The method of claim 82 further comprising solidifying the resin
on a peripheral surface of the mold roll and then stripping the
resin and attached electrical conductors from the mold roll.
84. The method of claim 83 wherein solidifying the resin comprises
forming fastener stems integrally molded with and extending from a
resin base.
85. The method of claim 84 wherein forming fastener stems
comprising molding fastener stems with integrally molded loop
engageable heads.
86. The method of claim 82 further comprising guiding the
electrical conductors into alignment with the grooves using a guide
plate.
87. The method of claim 82 wherein each groove is sized to receive
the aligned conductor.
88. The method of claim 82 wherein introducing the moldable resin
into the nip comprises introducing the moldable resin into the nip
such that the resin separates adjacent electrical conductors.
89. The method of claim 82 wherein attaching the electrical
conductors to the resin comprises encapsulating the electrical
conductors in the resin.
90. A method of forming a laminate with fastener elements, the
method comprising: introducing a substrate into a nip defined
between a mold roll and a pressure roll, the mold roll including
mold cavities defined in a peripheral surface of the mold roll;
introducing moldable resin into the nip under conditions such that
at least a portion of the resin enters the mold cavities while
encapsulating at least surface features of the substrate with the
resin; forming features integrally molded with and extending from a
resin base; solidifying the resin to form a laminate including the
resin base and the substrate; and then removing the laminate from
the mold roll; wherein the pressure roll defines a groove that aids
in aligning the substrate in the nip.
91. The method of claim 90 wherein the substrate comprises an
electrical conductor.
92. The method of claim 90 wherein introducing the substrate
comprises aligning the electrical conductor with the groove.
93. The method of claim 90 wherein the pressure roll defines a
plurality of grooves and introducing a substrate comprises
introducing multiple parallel substrates into the nip with each of
the parallel substrates aligned with a corresponding one of the
plurality of grooves.
94. The method of claim 93 wherein the multiple parallel substrates
each comprise an electrical conductor.
95. The method of claim 94 further comprising guiding multiple
electrical conductors into alignment with the grooves using a guide
plate.
96. The method of claim 94 wherein the conductors comprise
wire.
97. The method of claim 90 wherein forming the features comprise
forming stems of fastener elements.
98. The method of claim 97 wherein forming the stems comprises
molding loop engageable heads on the fastener stems.
99. The method of claim 90 wherein the groove substantially
circumferentially extending around a diameter of the pressure
roll.
100. The method of claim 90 wherein solidifying the resin comprises
solidifying the resin on the mold roll with the resin and substrate
remaining on the peripheral surface of the mold roll through a
partial rotation of the mold roll.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of and claims priority
under 35 U.S.C. .sctn.120 to PCT Application Serial No.
PCT/US01/46045, filed Oct. 25, 2001, which claims priority to U.S.
Provisional Application Ser. No. 60/293,743, filed May 25, 2001,
U.S. Provisional Application Ser. No. 60/323,244, filed Sep. 19,
2001, and U.S. Provisional Application Ser. No. 60/243,353, filed
Oct. 25, 2000, the entire contents of all four being hereby fully
incorporated by reference.
TECHNICAL FIELD
[0002] This invention relates to electrical cables and circuits,
and more particularly, to electrical cables and flexible circuits
incorporating hook and/or loop fasteners.
BACKGROUND
[0003] The use of electrical wires, cables and circuits throughout
the world has become increasingly prevalent. With this growth has
come the need to controllably direct and secure the routing of such
conductors and processors to avoid electrical injury to people and
to protect the electrical connections formed by such conductors
from being inadvertently disconnected or worn during assembly and
use.
[0004] For example, it is common in the automotive and other
industries to position electrical cables, e.g., dome lamp cables,
on the "non-show" surface (the surface not visible to vehicle
passengers) of trim panels, e.g., headliners, to provide power for
accessories, e.g., a dome lamp positioned within the headliner.
Often it is desirable to secure such electrical cables in place to
locate cable terminals for connection after trim panel installation
and to prevent noise and cable fatigue associated with cable
movement during the life of the assembly.
[0005] Ribbon cables, for example, are often employed within
computers and other electronic devices where it is advantageous to
secure the cables to, e.g., side panels, for ease of assembling
other internal components, to avoid damage to the cables during
assembly, and to reduce movement of the cables during use of the
products to avoid wear and fatigue.
[0006] Electrical circuit boards and appliances often include a
great number of electrical components interconnected for
communication of electrical signals. Such interconnections
typically require reliable connectors conducive to electrical
conductivity that are installed and assembled by various means
including, for example, soldering or plug and socket type
engagement. These methods of installation and assembly often
require precise alignment of mating pieces that are difficult to
move and adjust when reconnection is required after initial
assembly. It would be helpful if the fasteners provided secure yet
releasable attachment and if they allowed for quick and efficient
assembly without requiring precise alignment of the components to
be interconnected.
[0007] Furthermore, it is common to secure electrical cables within
the housings of computer hardware and peripheral equipment, within
appliance housings and behind trim panels of automobiles by using
various straps, adhesives, and other fastening materials and
techniques. Often, electrical cables are secured in place to locate
cable terminals for connection after trim panel installation and to
prevent noise and cable fatigue associated with cable movement
during the life of the assembly. Touch fasteners provide a
convenient means of securing cables to side panels, for example,
for ease of assembling other internal components, to avoid damage
to the cables during assembly, and to reduce wear-inducing movement
of the cables during use of the products.
SUMMARY
[0008] The invention features a cable or flexible circuit board
with permanently attached fastener means extending along its length
for securing the cable to a supporting surface.
[0009] According to one aspect of the invention, an elongated
electrical cable includes at least two electrical conductors
extending longitudinally along the cable and an insulating body
encompassing and electrically isolating the conductors from one
another, the insulating body including an exposed surface having an
array of fastener elements extending therefrom, the fastener
elements arranged and constructed to engage mating fastener
elements associated with a supporting surface to selectively secure
the cable to the supporting surface.
[0010] Variations of this aspect of the invention may include one
or more of the following features. The fastener elements are shaped
to engage exposed loop fibers associated with the supporting
surface. The exposed surface of the insulating body includes a
first broad surface of thermoplastic resin, the array of fastener
elements being made up of raised projections of the thermoplastic
resin. The exposed surface further includes a second broad surface
of thermoplastic resin, a second array of fastener elements made up
of raised projections of the thermoplastic resin extending from
said second broad surface. The array of fastener elements is
substantially coextensive with the first broad surface of the
insulating body. The field of fastener elements forms a
longitudinal band of fastener elements extending between lateral
edge regions of the cable, the lateral edge regions being void of
said fastener elements. The elongated electrical cable has an
entire thickness, measured from distal ends of the fastener
elements to an exposed broad surface of the insulating body
opposite the fastener elements, of less than about 0.050 inch. The
entire thickness is less than about 0.03 inch. The insulating body
is a laminate, the laminate including a first and a second layer of
thermoplastic resin and an adhesive layer disposed therebetween,
the first layer defining a first broad surface of the exposed
surface, the second layer defining a second broad surface of the
exposed surface, the array of fastener elements being made up of
raised projections of the thermoplastic resin of at least one of
the first and the second broad surfaces. The insulating body is a
unitary structure of thermoplastic resin, the unitary structure
defining a first and a second broad surface of the exposed surface,
the array of fastener elements being made up of raised projections
of the thermoplastic resin of at least one of the first and the
second broad surfaces. The insulating body includes a first and a
second layer of thermoplastic resin with the conductors disposed
therebetween, the first and second layers being permanently welded
to one another in a manner to encompass and electrically isolate
the conductors from one another, the array of fastener elements
being made up of raised projections of the thermoplastic resin of
an exposed surface of one of the first and second layers.
[0011] Yet additional features of this aspect of the invention may
include one or more of the following. The fastener elements are
exposed loop fibers. The insulating body includes a thermoplastic
resin and the exposed loop fibers are part of a web of fibers, the
web being attached to the insulating body by encapsulation of
fibers of the web by the thermoplastic resin. The web of fibers is
a nonwoven material. The elongated electrical cable defines a fixed
cable length between opposite longitudinal ends, the cable further
including an electrical connector electrically attached to at least
one of the conductors and mechanically attached to the cable at one
of the longitudinal ends.
[0012] In another aspect, the invention provides a releasably
securable ribbon cable extending to define a longitudinal
direction, the cable including a plurality of longitudinally
extending electrical conductors, an insulating body encompassing
and electrically isolating the plurality of conductors from one
another, and a strip of loop-engageable fastener elements formed of
thermoplastic resin, the strip extending longitudinally along the
ribbon cable and being permanently attached to a surface of the
insulating body such that the fastener elements are exposed for
engagement with a loop material.
[0013] Another aspect of the invention provides a method of
continuously forming an electrical cable, the method including:
[0014] introducing an electrical insulating material comprising a
thermoplastic resin into a gap formed adjacent a peripheral surface
of a rotating mold roll, the mold roll defining an array of
cavities therein, the insulating material being introduced under
pressure and temperature conditions selected to cause the
insulating material to at least partially fill the cavities to form
fastener element stems integrally with and extending from one broad
side of a strip of said insulation material; while [0015]
introducing at least two longitudinally continuous and spaced apart
electrical conductors to the gap so as to cause the insulating
material to envelop and electrically isolate the conductors and
cause the conductors to become an integral part of the strip of
insulation material from which the fastener element stems
extend.
[0016] Variations of this aspect of the invention may include one
or more of the following features. The cavities of the mold roll
are shaped to mold distal heads on the fastener element stems, the
distal heads being shaped to overhang the broad side of the strip
of insulating material so as to be engageable with exposed loop
fibers. Each of the stems defines a tip portion, the method further
comprising deforming the tip portion of a plurality of the stems to
form engaging heads overhanging the broad side of the strip of
insulating material, the engaging heads being shaped to be
engageable with exposed loop fibers. The gap is a nip defined
between the rotating mold roll and a counter-rotating pressure
roll. The gap is a nip defined between the rotating mold roll and a
counter-rotating mold roll, each of the rotating mold roll and the
counter-rotating mold roll defining an array of cavities therein,
the insulating material being introduced under pressure and
temperature conditions selected to cause the insulating material to
at least partially fill the array of cavities of each of the
rotating and the counter-rotating mold roll to form fastener
element stems integrally with and extending from each of opposite
broad sides of the strip of the insulation material. The insulating
material includes a layer of thermoplastic resin and a film backing
carrying the electrical conductors on a surface thereof, the layer
of thermoplastic resin being introduced to the gap directly
adjacent the rotating mold roll, the film backing carrying the
electrical conductors being introduced to the gap under pressure
and temperature conditions which cause the film backing to become
permanently bonded to the thermoplastic resin to envelop and
electrically isolate the conductors. The insulating material
includes a first and a second film of thermoplastic resin, wherein
the electrical conductors and the first and second films are
introduced to the gap with the electrical conductors disposed
between the first and the second film, said first film being
introduced directly adjacent the rotating mold roll under
temperature and pressure conditions that cause the first and second
films to become permanently bonded to each other in a manner
enveloping and electrically isolating the conductors. The method
includes, downstream of the gap, longitudinally severing the
electrical insulation material after solidification to form two
electrical cables, each cable containing at least one
conductor.
[0017] In another aspect, the invention provides a method of
continuously forming an electrical cable, the method including:
[0018] introducing molten resin into a nip formed between a
rotating mold roll and a counter-rotating pressure roll, the mold
roll having a peripheral surface defining an array of blind molding
cavities therein, under pressure and temperature conditions
selected to cause the resin to fill the mold cavities and form an
array of fastener element stems integrally molded with and
extending from a broad strip of resin; while [0019] simultaneously
introducing a preformed electrical ribbon-type cable to the nip
adjacent the pressure roll, such that the broad strip of resin
becomes permanently bonded to a broad side of the ribbon-type cable
on a side opposite the fastener element stems.
[0020] In another aspect of the invention, a method of continuously
forming an electrical cable includes: [0021] providing a fastener
tape of continuous length, the fastener tape comprising a base and
an array of loop-engageable fastener elements, the base being of
thermoplastic resin and defining a first and a second opposite
broad surface, the array of loop engageable fastener elements
comprising protrusions of the thermoplastic resin of the first
surface; [0022] arranging a backing film of continuous length
adjacent the fastener tape, the backing film defining a broad
surface, the broad surface of the backing film being arranged to
face the second broad surface of the fastener tape; [0023]
disposing a plurality of spaced apart electrical conductors of
continuous length between the second broad surface of the fastener
tape and the broad surface of the backing film; and [0024]
disposing a layer of electrically insulating adhesive between the
second broad surface of the fastener tape and the broad surface of
the backing film to cause the layer of adhesive to electrically
isolate the plurality of conductors from one another while
permanently bonding the fastener tape to the backing film to
envelop the plurality of conductors therebetween.
[0025] In another aspect of the invention, a method of forming an
electrical cable includes: [0026] introducing a strip of molten
electrical insulation material into a gap formed adjacent a
peripheral surface of a rotating roll; while [0027] introducing a
continuous strip of loop material to the gap along the surface of
the roll, under conditions selected to cause the loop material to
become at least partially embedded in the electrical insulation
material to bond the loop material to the resin while leaving
hook-engageable fiber portions exposed for engagement; and [0028]
introducing at least two longitudinally continuous and spaced apart
electrical conductors to the gap so as to cause the insulating
material to envelop and electrically isolate the conductors in the
gap to form a multi-conductor electrical cable having engageable
loops extending from an outer surface thereof.
[0029] Cables (or wires) having integral fastening means can obtain
numerous advantages. For example, continuous lengths of such
fastener-bearing cable can be cut to any desired length and still
retain its fastening properties. Additionally, the conductors can
provide longitudinal reinforcement for the fastener base. The cable
can be fashioned with a very low overall thickness, providing
flexibility for easy routing, low bulkiness and associated material
cost, and ease of cable concealment (e.g., for routing behind
automotive interior panels). Furthermore, the invention can provide
a fastenable cable without the structural redundancy of the
fastener base and cable insulator.
[0030] In another aspect of the invention, a strip-form layer of
electrical insulation having a pattern or circuit of conductive
material disposed on one surface thereof (or fully insulated
thereby, as in a flexible cable containing circuitry components) is
fed through a hook-forming nip as described with reference to any
of the above methods to form a hook-bearing layer integrally with
the strip-form layer of electrical insulation.
[0031] In yet another aspect, the invention is a product formed by
the method described immediately above.
[0032] In another aspect, the invention provides a flexible circuit
board including a substrate having first and second, opposite broad
surfaces, and a through-hole surface extending from the first to
the second broad surface defining a passage between the first and
second broad surfaces. The substrate further has an array of
fastener elements extending from the first broad surface, the first
broad surface and the array of fastener elements being formed
integrally of a thermoplastic resin. A pattern of electrically
conductive material is attached to the thermoplastic substrate, the
pattern encompassing at least a portion of the through-hole
surface.
[0033] This aspect of the invention may include one or more of the
following features. The pattern of electrically conductive material
is disposed only on the second broad surface and the at least a
portion of the through-hole surface. The pattern of electrically
conductive material is disposed only on the first broad surface and
the at least a portion of the through-hole surface. The pattern of
electrically conductive material encompasses at least a portion of
the array of hook fastener elements. The pattern of electrically
conductive material encompasses an entirety of the first or second
broad surface.
[0034] In another aspect of the invention, an electrical cable
includes a strip-form substrate having first and second, opposite
broad surfaces and an array of fastener elements extending from the
first broad surface. The first broad surface and the array of
fastener elements are formed integrally of a thermoplastic resin,
and a continuous strip of conductive material is attached to one of
the first and second broad surfaces, the continuous strip being
longitudinally coextensive with the strip-form substrate.
[0035] In another aspect of the invention, a method of forming an
electrically conductive hook tape includes providing a substrate
having first and second, opposite broad surfaces and an array of
fastener elements extending from the first broad surface, the first
broad surface and the array of fastener elements being formed
integrally of a thermoplastic resin; applying a sensitizer to an
exterior surface of the substrate; and applying a solution
comprising a conductive material to the exterior surface where the
sensitizer was applied, to produce a chemical reduction reaction
between the conductive material and the sensitizer wherein the
conductive material attaches to the exterior surface of the
substrate.
[0036] Variations of this aspect of the invention may include one
or more of the following features. A wetting agent is applied to
areas of the substrate to be coated with the conductive material
prior to application of the sensitizer. The sensitizer includes an
anodic material that is disposed on the external surface of the
substrate and the conductive material includes a cathodic material
relative to the anodic material. The sensitizer comprises tin and
the conductive material comprises silver. The solution further
comprises an activator. The activator solution further comprises a
reducer. The conductive material is applied to the first broad
surface of the thermoplastic substrate. The conductive material
coats at least a portion of the array of fastener elements. The
method further includes a step of masking selected regions of the
surface of the substrate prior to the step of applying sensitizer,
thereby preventing attachment of the conductive material in the
selected regions. The substrate further includes a through-hole
surface extending between the first and second broad surfaces to
define a passage. The conductive material is attached to at least a
portion of the through-hole surface.
[0037] Another aspect of the invention provides a method of forming
a flexible circuit board with integral hook fastener elements, the
method including introducing an elongated flexible circuit
including a substrate and at least one electrically conductive path
to a gap adjacent a peripheral surface of a mold roll, the mold
roll having hook fastener element stem forming cavities extending
inwardly from the peripheral surface, while simultaneously,
introducing a thermoplastic resin into the gap directly adjacent
the peripheral surface under temperature and pressure conditions
causing the thermoplastic resin to at least partially fill the stem
forming cavities and to permanently bond to the substrate. Finally,
the method includes stripping the permanently joined thermoplastic
resin and substrate from the mold roll to expose the fastener
element stems.
[0038] Variations of this aspect of the invention can include one
or more of the following additional features. The conductive path
is electrically insulated within the substrate prior to being
introduced to the gap. A portion of the conductive path is exposed
within the substrate for making an electrical connection with the
conductive path. The portion of the conductive path is exposed
prior to entering the gap. The portion of the conductive path is
exposed by partial removal of the substrate after stripping the
thermoplastic resin from the mold roll. The conductive path is
disposed on an exterior surface of the substrate prior to being
introduced to the gap, the thermoplastic resin being of an
electrically insulating material, the conductive path being
enveloped by the thermoplastic resin and the substrate. The
conductive path is comprised of continuous strips of conductive
material. The conductive path is comprised of discontinuous strips
of conductive material that are electrically joined by electrical
components.
[0039] In another aspect, the invention provides a securable
flexible circuit including a carrier substrate of thermoplastic
resin having a first broad surface and a second broad surface, the
first broad surface being exposed and having an array of hook
fastener elements protruding therefrom, the hook fastener elements
formed as raised projections of the thermoplastic resin of the
first broad surface, and an electrically conductive path disposed
on said second broad surface.
[0040] Variations of this aspect of the invention can include one
or more of the following features. The securable flexible circuit
further includes a backing substrate having a first broad surface
and a second broad surface, the backing substrate laminated to said
carrier substrate with said electrically conductive path disposed
between the second broad surface of the backing substrate and the
second broad surface of the carrier substrate.
[0041] The backing substrate includes an array of hook fastener
elements protruding from the first broad surface thereof. The
backing substrate defines through-holes extending from said backing
strip first broad surface to said backing strip second broad
surface, the through-holes exposing portions of the conductive
path. The securable flexible circuit further includes a layer of
adhesive disposed between the backing substrate and the carrier
substrate for lamination. The through-holes extend through the
layer of adhesive.
[0042] Electrically conductive hook fastener substrates of the
present invention provide for effective transmission of electrical
signals on a flexible medium that can be reliably and releasably
secured to a surface having complementary fastening material. In
the assembly of products that include electronic components, such
hook fastener substrates can be used, for example, as electrical
cables. Such cables offer the advantage of being readily secureable
to walls or other surfaces having complementary fastener materials.
This allows the cables to be routed and secured in a manner that
avoids interference with subsequent assembly operations and also
eliminates subsequent wear-causing movement of the installed cables
that may occur during use of the assembled product.
[0043] Such flexible conductive hook fastener substrates can be
efficiently and continuously formed with integral hook fastener
elements according to certain methods and apparatus of the
invention. These techniques allow for electrical conductivity along
the substrate in a patterned arrangement, on one or more surface,
and/or on the hook fastener members themselves, as desired.
Furthermore, the resulting conductive hook fastener substrates
provide a surface on which other electrical components can be
attached to process, relay, or modify electrical signals carried
along the substrate.
[0044] The conductive coating of the fastener product of the
present invention may be applied as an advantageously thin layer.
In certain embodiments, the conductive layer is of a thickness less
than 0.0015 inches (0.038 mm), while in other embodiments the
conductive layer is less than 0.0010 inches (0.025 mm). By applying
a thinner conductive layer, less weight is added in making the
fastener product conductive and less conductive material is
expended.
[0045] The details of one or more embodiments of the invention are
set forth in the accompanying drawings and the description below.
Other features, objects, and advantages of the invention will be
apparent from the description and drawings, and from the
claims.
DESCRIPTION OF DRAWINGS
[0046] FIG. 1 illustrates an electrical cable assembly secured to a
typical automobile headliner positioned within the cab of an
automobile.
[0047] FIG. 2 illustrates the headliner of FIG. 1 with the
electrical cable removed.
[0048] FIG. 3 is a highly enlarged view of area 3 of FIG. 2.
[0049] FIG. 4 illustrates a headliner similar to that of FIG. 2
with an alternative surface fastener.
[0050] FIG. 5 is a highly enlarged view of area 5 of FIG. 3.
[0051] FIG. 6 illustrates the electrical cable assembly of FIG. 1
detached from the headliner.
[0052] FIG. 7 is a cross-sectional view taken along line 7-7 of
FIG. 6.
[0053] FIG. 8 is a cross-sectional view similar to that of FIG. 7,
illustrating an alternative electrical cable for securing the
headliner of FIG. 4.
[0054] FIGS. 8A-8E illustrate various loop material attachment
alternatives.
[0055] FIG. 9 illustrates a first method and apparatus for forming
electrical cables with integral fasteners such as those illustrated
in FIGS. 7 and 8.
[0056] FIG. 9A is an enlarged view of the forming nip of the
apparatus of FIG. 9.
[0057] FIG. 10 illustrates a pre-formed electrical conductor
product.
[0058] FIG. 10A illustrates pre-formed loop material for forming
certain embodiments of electrical cables of the invention.
[0059] FIG. 11 is a highly enlarged view of the loop
material-securing region of the nip.
[0060] FIG. 11A is a view similar to that of FIG. 1, with a
modified mold roll.
[0061] FIG. 12 is an enlarged view of the outer edge of a staking
ring.
[0062] FIG. 13 illustrates a second method and apparatus for
forming electrical cables with integral fasteners such as those
illustrated in FIGS. 7 and 8.
[0063] FIG. 14 illustrates a third method and apparatus for forming
electrical cables with integral fasteners such as those illustrated
in FIGS. 7 and 8.
[0064] FIG. 15 illustrates an electrical device equipped with an
electrical ribbon cable having integral fasteners.
[0065] FIG. 16 illustrates the electrical ribbon cable assembly of
FIG. 15.
[0066] FIG. 17 illustrates a pre-formed electrical conductor
product used in the formation of the electrical ribbon cable of
FIG. 16.
[0067] FIG. 18 is a cross-sectional view of the electrical ribbon
cable, taken along line 18-18 of FIG. 16.
[0068] FIG. 18A is a cross-sectional view similar to that of FIG.
18, illustrating a variation of the electrical ribbon cable
structure.
[0069] FIG. 19 is schematic illustration of various methods for
producing elongated electrical cables of the invention.
[0070] FIG. 20 is an unscaled, diagrammatic, cross-sectional view
taken along line 20-20 of FIG. 19.
[0071] FIG. 20A is an unscaled, diagrammatic, cross-sectional view
taken along line 20A-20A of FIG. 20.
[0072] FIG. 21 is a view similar to that of FIG. 20 illustrating an
alternative elongated electrical cable.
[0073] FIG. 22 is a view similar to that of FIG. 20 illustrating an
intermediate product to be subsequently formed into an alternative
electrical cable of the present invention.
[0074] FIG. 22A is an unscaled, diagrammatic, cross-sectional view
taken along line 22A-22A of FIG. 19.
[0075] FIG. 23 is a schematic illustration of an alternative method
for manufacturing an electrical cable of the present invention.
[0076] FIG. 24 is an unscaled, diagrammatic, cross-sectional view
taken along line 24-24 of FIG. 23.
[0077] FIG. 25 is an unscaled, diagrammatic, cross-sectional view
taken along line 25-25 of FIG. 23.
[0078] FIG. 26 is a schematic, perspective view of an alternative
method for making an electrical cable of the present invention.
[0079] FIG. 27 is an unscaled, diagrammatic, cross-sectional view
taken along line 27-27 of FIG. 26.
[0080] FIG. 28 is a schematic illustration of a portion of a method
for manufacturing an alternative electrical cable of the present
invention.
[0081] FIG. 29 is an unscaled, diagrammatic, cross-sectional view
taken along line 29-29 of FIG. 28.
[0082] FIG. 30 is a schematic illustration of a portion of an
alternative method for manufacturing an electrical cable of the
present invention.
[0083] FIG. 31 is an unscaled, diagrammatic, cross-sectional view
taken along line 31-31 of FIG. 30.
[0084] FIG. 32 is an unscaled, diagrammatic, cross-sectional view
taken along line 32-32 of FIG. 30.
[0085] FIG. 33 is a magnified, diagrammatic, cross-sectional view
taken along line 33-33 of FIG. 30.
[0086] FIG. 34 is an unscaled, diagrammatic, cross-sectional view
similar to that of FIG. 29 of an alternative electrical cable of
the present invention.
[0087] FIG. 35 is a magnified view of a portion of a hook fastener
tape suitable for use in the present invention.
[0088] FIG. 35A illustrates a further magnified side view of a
single hook fastener element of the hook fastener tape of FIG. 35
having a layer of conductive coating.
[0089] FIG. 36 illustrates schematically a method and apparatus for
producing the hook type of FIG. 35 and a method and apparatus for
applying a conductive coating to selected areas of the fastener
tape.
[0090] FIGS. 37A, 37B, 37D and 37E illustrate a hook fastener tape
similar to that of FIG. 35 at various stages of the process
illustrated in FIG. 36.
[0091] FIG. 37C illustrates a masking film for use in the process
illustrated in FIG. 36 and used on the hook fastener tape of FIG.
37D.
[0092] FIG. 38A illustrates a flexible, electrically conductive,
hook fastener cable and a detachable corresponding electrical
component.
[0093] FIG. 38B is a magnified view of circle 38B of FIG. 38A.
[0094] FIGS. 39A, 39B and 39C illustrate top, side and bottom
views, respectively, of an alternative electrically conductive,
hook fastener cable.
[0095] FIGS. 40A and 40B illustrate side and bottom views,
respectively, of an alternative electrically conductive, hook
fastener cable with attached electrical components.
[0096] FIG. 41 illustrates a bottom view of an alternative
electrically conductive, flexible hook fastener circuit with
attached electrical components.
[0097] FIGS. 41A and 411B illustrate a bottom and a side view,
respectively, of a backing film, particularly for use with the
cables/circuits of FIGS. 39A, 39B, 40A, 40B and 41.
[0098] FIG. 41C illustrates a side view of a laminated flexible
circuit product combining the backing film of FIGS. 41A and 41B
with a cable/circuit of FIG. 39A, 39B or 40A, 40B, or 41.
[0099] FIG. 41D illustrates the flexible circuit product of FIG.
41C releasably secured to a supporting surface.
[0100] FIG. 42 illustrates a side view of an alternative
electrically conductive hook fastener tape having a conductive,
hook-engageable, loop material backing.
[0101] Like reference symbols in the various drawings indicate like
elements.
DETAILED DESCRIPTION
[0102] Referring to FIG. 1, automobile headliner 10 is positioned
within automobile 14 (shown with roof panel removed in FIG. 1) so
that dome lamp aperture 12 can receive a dome lamp (not shown). In
order to provide electricity to the dome lamp while remaining out
of view of automobile passengers for aesthetic and safety reasons,
flat electrical cable 30 is secured along the "non-show" surface 16
of headliner 10. Referring now also to FIG. 2, non-show surface 16
of headliner 10 is of a loop material capable of being engaged by
hook or mushroom shaped protrusions to form hook and loop
engagement as described below. The loop material may be a
non-woven, knit, or other fibrous material capable of engaging
protrusions as described below, and may be of the same material as
the opposite, "show" surface, of headliner 10. Alternatively,
smaller patches (not shown) of loop material may be positioned on
non-show surface 16 in areas selected for cable 30 attachment. As
illustrated in FIG. 3, loop material on non-show surface 16 of
headliner 10 is a non-woven mat of tangled fibers, which allow
penetration and engagement by protrusions to achieve fastening.
Suitable loop materials are further discussed below.
[0103] FIG. 4 illustrates an alternative arrangement wherein
headliner 10' has a non-show surface 16' without engageable fibers
or loops. Non-show surface 16' is instead provided with hook arrays
24 along the desired path for electrical cable securement. As
illustrated in FIG. 5, hook arrays 24 consist of multiple
individual hook-shaped protrusions which can be formed integrally
with non-show surface 16 during manufacture of headliner 10' or can
be applied with adhesive or otherwise after formation of headliner
10'. A suitable protrusion shape is the CFM29 hook shape (of about
0.015 inch in height, h (FIG. 7), available in various products
sold by Velcro USA of Manchester, N.H. Alternative protrusion
shapes, such as mushrooms, palm trees, flat-topped hooks, or other
loop engageable shapes are also suitable. Hook height, h (FIG. 7),
is typically within the range of 0.003 to 0.03 inch.
[0104] Electrical cables of the invention and their securement to a
panel, e.g., headliners 10, 10', will now be described. As
illustrated in FIG. 6, electrical cable 30 has a plastic base strip
40 carrying two attached flat conductive strips 36 for delivering
electrical signals between terminal electrical connectors 32.
Electrical connectors 32 are provided for connection to mating
electrical connectors, e.g., a dome lamp connector and an A-pillar
connector (not shown) to complete a desired electrical circuit.
Securing surface 42 of electrical cable 30 has an array of
hook-shaped protrusions 34, similar to those illustrated in FIG. 5
and described above, for engaging loop material of a mating panel,
e.g., loop material of non-show surface 16 of headliner 10 as
described above (FIGS. 2,3). Hooks 34 are formed integrally from
the same material as plastic base strip 40 as described below. As
illustrated in FIG. 7, electrical cable 20 also includes a backing
of electrical conductor insulator material 38 to protect and
insulate conductors 36. The overall thickness, t, of cable 20, as
measured from distal ends of the hooks to an exposed broad surface
of the insulator backing 38 opposite the fastener elements, is
typically much less than 0.10 inch. In fact, in most embodiments
thickness t is less than 0.05 inch and in some embodiments, less
than 0.03 inch.
[0105] FIG. 8 illustrates the cross-section of an alternative
electrical cable 30', suitable for use with hook-bearing panels,
e.g., headliner 10' (FIGS. 4 and 5). Plastic base strip 40 carries
electrical conductors 36, insulation material 38, and exposed loop
material 44 suitable for engagement by hooks similar to those
illustrated in FIG. 5 and described above. In one embodiment loop
material 44 is a non-woven mat of tangled fibers similar to those
illustrated in FIG. 3 and described above. Suitable loop materials
and methods and apparatus for their production are disclosed in
U.S. patent application Ser. No. 09/262,159, filed Mar. 3, 1999, to
which the reader is referred for further information. Other
non-woven, knit, or fibrous materials capable of engaging
protrusions described above are also suitable.
[0106] Preferably, the non-woven loop material 44 is very thin,
such as less than about 0.040 inch thick (more preferably, less
than about 0.020 inch thick), with web fibers held in a
transversely stretched condition and freestanding loop structures
extending from its exposed surface. As discussed in the
above-referenced patent application, the loop structures extend
from associated knots in the stretched web, which may be stabilized
by liquid binder wicked into the knots and cured. Between knots,
the thin fiber mat is not very dense and is sheer enough to permit
images to be readily seen through it. Overall, the loop material
has a basis weight (in its preformed state, including any
pre-applied binder) of less than about 4 ounces per square yard
(136 grams per square meter), preferably less than about 2 ounces
per square yard (68 grams per square meter). Other details of this
loop material may be found in the above-referenced application. For
applications in which the loop material is partially penetrated by
resin of the substrate as the substrate is formed (as discussed
below), the needled loop material is preferably only stretched in a
transverse direction only about 22 percent to leave a fair amount
of loft and avoid total penetration.
[0107] Some lightweight knits are also suitable loop materials for
certain applications. Examples of such knits are Product 19902 from
Guilford Knits in Greenville, S.C., which is of polyester fibers
and has a basis weight of only about 1.6 ounces per square yard.
For a heavier knit, Guilford's Product 20229, a nylon knit of about
3.3 ounces per square yard is suitable. Lightweight knit products
are also available from TYBOR in Spain, and MIZARD in Italy.
[0108] In some instances, loop material 44 is partially
encapsulated directly in resin of plastic base strip 40 as the
substrate is formed in a continuous molding process (described
below). In other cases, it is bonded to the formed substrate,
either by ultrasonic bonding, welding, or adhesives.
[0109] FIGS. 8A through 8E illustrate various patterns of variable
bonding between loop material 44 and substrate 40. For simplicity,
electrical conductors 36 (FIG. 8) are not shown. The variable
bonding patterns correspond, in some cases, to variable resin
penetration into the web of the loop material, which may be
achieved by employing different arrangements of staking rings
and/or barrier materials between the loop material and substrate,
both of which are discussed further below. In FIG. 8A, loop
material 44 is only fully penetrated by substrate resin in narrow
edge regions 52, and is less penetrated at its center. For
instance, if loop material is about 3/4 inch wide (W.sub.L), then
fully penetrated edge regions 52 may have a width (w.sub.e) of only
about 1/8 inch. The center region of the loop material is less
penetrated and gently arches away from the substrate, presenting
the loops for engagement. The inclined sides of the center arch can
also help to enhance the peel strength of the fastening at the
edges of the loop material, as they resolve a small component of
the peel force in a tangential, or shear, direction.
[0110] The pattern of variable bonding shown in FIG. 8B creates
transverse pillows 54 of relatively lightly bonded, or loose, loop
material separated by transverse bands 56 of relatively more fully
bonded (e.g., more deeply encapsulated) loop material. The
loftiness of pillows 54 is exaggerated for illustration. This
pattern enhances initial peel strength of the fastening, as the
"free" pillow ends along the inner and outer edges of the loop
material follow the mating fastener elements, e.g., hooks, during
peel until they are separated in sheer.
[0111] FIG. 8C illustrates a bonding pattern with longitudinal
pillows 58 of relatively lightly bonded, or loose, loop material,
separated by longitudinal bands 60 of relatively more fully bonded
(e.g., more deeply encapsulated) loop material. Again, the
loftiness of the pillows is exaggerated for illustration. FIG. 8D
is a variation of the pattern of FIG. 8C, with each longitudinal
band of more fully bonded material separated into longitudinally
alternating regions of light and heavy bonding. The regions of
light and heavy bonding are staggered across the loop material,
producing a checkerboard pattern of lofted loop pillows. FIG. 8E
shows a bonding pattern with edge regions 62 of alternating light
and heavy bonding, and a center region bonded in only isolated
regions 64. The bonding patterns described above may be mixed and
varied for different applications, as required.
[0112] FIG. 9 illustrates multiple methods and apparatus for
producing the above described electrical cables. The methods build
upon the continuous extrusion/roll-forming method for molding
fastener elements on an integral, sheet-form base described by
Fischer in U.S. Pat. No. 4,794,028, and the nip lamination process
described by Kennedy et al. in U.S. Pat. No. 5,260,015. The reader
is referred to both of these publications for further information.
The relative position and size of the rolls and other components is
not to scale. An extrusion head 100 supplies a continuous sheet of
molten resin 140 to a nip 102 between a rotating mold roll 104 and
a counter-rotating pressure roll 106 (nip arrangement illustrated
in FIG. 9A). Mold roll 104 contains an array of miniature, fastener
element--shaped mold cavities 134 extending inward from its
periphery for molding the fastener protrusions, e.g. 34 (FIG. 7).
Pressure in nip 102 forces resin into the fastener element cavities
and forms the substrate (base 40, FIGS. 7, 8). The formed product
is cooled on the mold roll until the solidified fastener elements
(e.g., hooks) are stripped from their fixed cavities by a stripper
roll 108. Along with the molten resin, a continuous strip of
electrical conductor product 110 (illustrated in cross-section in
FIG. 10), including insulator tape 38 with attached electrical
conductor strips 36 is fed into nip 102, where it is bonded with
resin 140 and becomes permanently secured to the front face of the
substrate 40. Thus, the product 162 that is stripped from the mold
roll 104 includes both fastener elements 34 and electrical
conductor strips 36 as illustrated, for example, in FIG. 7
described above.
[0113] For higher production rates, two or more electrical cables
may be simultaneously produced on a single mold roll, and later
split and spooled. Referring again to FIG. 10, continuous strip of
electrical conductor product 110 is provided having two (or more,
if desired) electrical cable profiles joined side by side (a second
cable profile indicated by dashed lines in FIG. 10), each cable
profile bearing the desired number and arrangement of conductive
strips 36. The electrical conductor product is fed into nip 102 and
molten resin is introduced across the entire nip, impregnating and
forming hooks along the entire multiple-cable-width strip of
electrical conductor product 110. A protruding splitting channel
ring 118 (FIG. 9A) (or multiple rings if more than two profiles are
provided) at the center of the mold roll (or spaced according to
the width of the individual cable profiles) produces a splitting
channel in the product, along which the resulting tape is split by
a blade 120 (FIG. 9; either stationary or rotating) into two (or
more) separate runs of electrical cable which are separately
spooled.
[0114] FIG. 9 indicates several variations of the above-described
method. For instance, rather than introduce the electrical
conductor product 110 through nip 102 and thereby join it to the
substrate as the substrate is molded, the electrical conductor
product may be joined to the substrate after the substrate has been
formed, such as is indicated by the run 110' of electrical
conductor product shown in dashed outline. In this case, front face
idler 122 is heated and has a contoured surface to bond the
electrical conductor product and the substrate in desired areas
while not damaging the molded hooks.
[0115] FIG. 9 also illustrates a method and apparatus for producing
a flat electrical cable having engageable loops on one surface for
cable securement, as for example the electrical cable illustrated
in FIG. 8 and described above. In this method, electrical conductor
product 110 is fed into nip 102 along with extruded resin 140. Nip
102 is formed between mold roll 104 and pressure roll 106, but in
this embodiment, mold roll 102 lacks element-forming mold cavities.
A continuous strip of loop material 144, illustrated in FIG. 10A
and, for example, as described above in reference to FIG. 8, is
simultaneously fed into nip 102. The electrical conductor product
110 and the loop material 144 are bonded to the resin of the
substrate by pressure in the nip 102.
[0116] Applying even pressure across nip 102 may lead to excessive
resin penetration, or "flooding" of the loop material 144, which
may reduce loop loft and have an adverse effect on fastener
performance. In one embodiment, to avoid excessive resin
penetration, mold roll 104 has staking rings 130 (FIG. 11) of
increased diameter relative to a central portion(s) 132 of mold
roll 104 to engage and locally hold the edges of the insulator
material of the conductor product and the loop material against the
extruded resin as the resin forms the substrate under nip pressure,
thereby ensuring heavy penetration of the insulator and loop
materials in predetermined areas along the cable edges. This
configuration shown in FIG. 11 produces the bonding pattern
illustrated in FIG. 8A, the staking rings 130 forming heavily
bonded edge regions 52 corresponding to the width of mold roll
staking rings 130. If multiple cable strips are being produced
simultaneously on the same mold roll, multiple sets of such staking
rings can be employed to heavily penetrate the conductor product
and loop material adjacent to each splitting ring 118 (FIG. 9A,
described above). Alternatively or additionally, the mold roll may
be provided with a pattern or series of protruding surfaces to form
a pattern of heavily bonded areas across each cable product. These,
heavily bonded areas can be formed by such rings or protrusions on
the mold ring, the pressure ring or a combination of both.
[0117] To form a row of heavily bonded points separated by regions
of lower resin penetration, some staking rings 130 have a contoured
outer edge as shown in FIG. 12. A series of protrusions 134
extending beyond the nominal diameter D.sub.s of the staking ring
cause the resin to locally penetrate farther into the loop
material. In this example configuration, D.sub.s is 9.968 inches,
the height (h.sub.s) of each protrusion 134 is 0.014 inch, and the
inner and outer radii (R) at the flank of each protrusion is 0.015
inch. The protrusion pitch (P.sub.s) is 0.202 inch, and the length
of the flat between protrusions (w.sub.f) is 0.130 inch. The
dimensions of the protrusions are selected to attempt to optimize
the maximum approach angle .alpha..sub.f of the protrusion flank
with respect to a local ring tangent. A steep approach angle (i.e.,
an abrupt change in ring diameter) can cause a sharp local increase
in nip pressure and an undesirable local flooding of the front side
of the loop material with resin. Such flooded areas can create
local "depth stops" to mating fastener elements, reducing the
fastener element penetration into the loop material. A zero
approach angle (i.e., no protrusions) would result in a homogeneous
resin penetration beneath the staking ring, which may not be as
desirable as local loop material "pillowing" (discussed above) in
some applications. The maximum approach angle .alpha..sub.f in the
illustrated staking ring embodiment is about 40 degrees. A
shallower angle (e.g., of about 30 degrees) may be preferable in
some cases, as may a longer spacing w.sub.f between protrusions to
provide longer, lofted pillow regions.
[0118] FIG. 11A shows a staking ring configuration for producing
the bonding pattern shown in FIG. 8D (electrical conductor product
110 not shown). Staking rings 136 having the profile shown in FIG.
10 are stacked together with staggered protrusions, such that the
pattern of heavily bonded regions resembles a checkerboard with
elongated "pillows" extending outward between the heavily bonded
regions. The width w.sub.s of each ring is about 0.018 inch.
[0119] In another embodiment, also illustrated in FIG. 9, excessive
resin penetration of loop material 144 is avoided by providing a
barrier layer 128 between the resin and the loop material. Barrier
material 128 is, in some instances, a perforated paper or film that
allows resin to pass into the loop material in selected regions but
inhibits its flow into other regions, such as for producing the
bonding pattern of the center region of loop material shown in FIG.
8E. The barrier material may also be a homogeneous sheet of
material having a high porosity, equally limiting the penetration
of resin into the loop material across the width of the barrier
material. Rather than be introduced as a separate sheet, in some
cases the barrier material is pre-applied to the surface of loop
material 110 and may be in the form of a binder located in discrete
areas of the loop material and locally encapsulating fibers of the
loop material, for instance. In many cases, the barrier material is
narrower than the loop material, and centered along the width of
the loop material, to enable full penetration of resin into the
edges of the loop material. In all cases in which the barrier
material becomes permanently bonded to the substrate and therefore
becomes an integral part of the final product, it should be
selected for its low material cost and weight.
[0120] FIG. 13 illustrates an alternative method and apparatus for
forming the above-described electrical cables. The contoured
surface of an extrusion head 200 (sometimes called an injection
head) is placed adjacent a mold roll 104 (mold roll 104 once again
lacking fastener protrusion shaped cavities to produce the loop
bearing conductor cable of FIG. 8), and a continuous flow of molten
resin is injected under pressure into the gap 202 defined between
head 200 and mold roll 104, filling gap 202 and forming the front
and back faces of the substrate. The configuration and construction
of mold roll 104 is the same as is shown in FIG. 8, in which member
106 may be taken to be the adjoining extrusion head. To create the
loop bearing electrical cable such as that illustrated in FIGS.
8-8E and described above using this method and apparatus the strip
144 of loop material is fed through a predetermined region of gap
202, and held up against the surface of mold roll 104 by resin
pressure in the gap. In applications where it is not possible to
fill gap 202 without completely saturating loop material 144 with
resin, a strip of barrier material 128 may be fed through gap 202
between head 200 and loop material 110 to prevent resin penetration
of the loop material along predetermined regions. Barrier material
128 is discussed in more detail above with respect to FIG. 9.
Electrical conductor product 110 is laminated to the back face of
the substrate while the molded product is retained on mold roll
104, by pressure supplied by pressure roll 206.
[0121] FIG. 13 also illustrates an alternative method and apparatus
for producing the fastener protrusion bearing conductive cable
illustrated in FIG. 7. In this embodiment loop material 144 and
barrier material 128 are not present and mold roll 104 has fixed
fastener element molding cavities as described above with respect
to FIG. 9. Resin alone is fed through extrusion head 200 into gap
202 between extrusion head 200 and mold roll 104 where gap pressure
forces the resin to fill the mold cavities as previously described.
Electrical conductor product 110 is laminated to the back face of
the substrate while the molded product is retained on mold roll
104, by pressure supplied by pressure roll 206 to produce an
electrical cable strip bearing protruding fastener elements.
[0122] In an alternative method and apparatus illustrated in FIG.
13, electrical conductor product 110'' (as indicated by dashed
lines) is fed directly into gap 202. Electrical conductor product
110'' consists of either bare or insulated strands of electrical
conductor (as described below with reference to FIG. 14) or has a
backing of at least sufficient porosity that resin introduced to
gap 202 flows at least partially through or around the electrical
conductor product to insulate the conductors and bond the materials
to form an integral cable product.
[0123] FIG. 14 illustrates an additional method and apparatus for
producing the above described electrical conductor cables. In this
embodiment extruder head 300 supplies resin flows or films 140, 141
into nip 102 formed by mold roll 104 (the mold roll having fixed
fastener element molding cavities 155 as described above with
respect to FIG. 9 to produce a cable product such as that
illustrated in FIG. 7) and pressure roll 106, respectively. The
arrangement of nip 102 is as described above in reference to FIGS.
9 and 9A. Simultaneous with the resin feed, multiple strands of
bare conductive material 310 are fed through an extrusion die of
extruder head 300 into nip 102 between the separate resin flows or
films 140, 141. Pressure and temperature conditions in nip 102
force resin flow or film 140 to flow into the molding cavities as
described above, encapsulates conductive material 310 within resins
140, 141, and bonds separate resin flows or films 140, 141 to
create an integral cable product having conductors insulated within
a substrate and fastener protrusions extending from a surface of
the substrate.
[0124] The method and apparatus illustrated in FIG. 14 are also
capable of producing cable product such as that illustrated in FIG.
8 and described above. In such an arrangement mold roll 102 lacks
fastener protrusion shaped cavities and loop material 144 (shown as
dashed lines in FIG. 14) as described above in reference to FIG. 8
is fed directly on to the surface of mold roll 102 prior to the
entrance of resin flow 140 into nip 102. As described above with
reference to FIGS. 9 and 13, staking rings, barrier layers, or both
may be used to control the areas and amounts of resin 140
penetration into loop material 144 to bond the materials.
[0125] The methods and apparatus of FIGS. 9, 13, and 14 are also
capable of forming electrical cables having both fastener
protrusions (e.g., hooks or mushrooms) and loop fastener material
capable of engaging the protrusions to form a fastening. Using the
above described techniques wherein mold roll 104 has fastener
protrusion forming cavities and loop material 144 is fed into the
nip or gap while resin and electrical conductor product are
introduced yields a self-engageable electrical cable product having
both types of fastener elements.
[0126] As illustrated in FIG. 15, ribbon cable assembly 330 is
secured within computer casing 309 with terminal ends 332 connected
to internal components 333 and 334 to deliver power or electrical
communications signals therebetween. Referring now also to FIG. 16,
cable assembly 330 has a multiplicity of conductor strands 336
within an insulating substrate 338 which has fastener elements 334
similar to those described above with reference to FIG. 7 on its
surface. Panel 311 of computer casing 309 has mating fastener
elements, e.g., loops 316, such as those described above with
reference to FIGS. 2 and 3. During assembly of the computer,
terminals 332 are first connected to internal components 333, 334
respectively. The fastener elements 334 of cable assembly 330 are
then adjustably and releasably engaged with mating fastener
elements, e.g., loops 316, on panel 309. This allows for easier
entry or removal of additional computer components, e.g., boards
313, 314, within computer casing 309, and keep the cable layout
within the cabinet organized.
[0127] Any of the methods and apparatus described above with, e.g.,
reference to FIGS. 9, 13, and 14 can be used to create a continuous
strand of ribbon cable for use in ribbon cable assemblies (e.g.,
assembly 330) with attached fastener elements, e.g., hooks 334 or
loops (not shown). In one example illustrated in FIG. 17 preformed
electrical conductor product 410 is provided having multiple
conductive wires 336 attached to insulating tape 338. Wires 336 can
be of circular, or flattened rectangular or other flattened
cross-section, of stranded construction, or can be strips of
conductive material deposited or otherwise disposed on insulating
tape 338. In one embodiment, the conductors 336 are strips
deposited on backing tape 338 to form a circuit or other conductive
path. For example, any of the strip-form products described herein
(particularly, but not exclusively, the products illustrated in
FIGS. 40 and 41) can be fed through a hook forming nip (as
described above) to form a layer of hook-bearing thermoplastic
resin either as an electrical insulation layer immediately adjacent
the conductors, or as a layer joined integrally to a pre-existing
electrical insulation layer. For example, flexible cable containing
circuitry, such as embedded surface-mount components or other
electronic devices, can be fed directly through the nip to form
hooks on one side of the circuit cable. In another embodiment, the
backing tape 336 is, itself, a pre-formed hook tape (similar to
layer 140), the conductors 336 being disposed on a surface of the
hook tape opposite the hooks.
[0128] Conductor product 410 along with plastic resin 140 is fed
through a nip or gap to form a cable wherein the resin forms molded
fastener elements 334 and attaches to insulator tape 338 thereby
insulating multiple conductive wires 336 and producing the integral
fastener-cable of FIG. 18. Alternatively, loop material 144 (not
shown) and resin are simultaneously fed into the nip of one of the
above described apparatus (wherein the mold roll does not have
fastener forming cavities) such that the resin bonds to the
insulator tape 338 to insulate multiple conductive wires 336 and at
least partially penetrates loop material 144 to form the continuous
strand of conductive cable (as described above with reference to
FIGS. 9, 13).
[0129] In another example illustrated in FIG. 18A, pre-formed
ribbon cable 510 has multiple conductors 336, fully insulated by
insulator material 338. Pre-formed ribbon cable 510 is fed into nip
102 (FIGS. 9, 13, 14), as element 110 or 310, respectively, and
fastener elements (fastener protrusions 334 or loop material, not
shown) are bonded to at least a portion of a surface of ribbon
cable 510. In this manner, a fully pre-formed ribbon cable can be
modified to have attached fastener elements molded thereon for use
in assembly of electronic products.
[0130] Referring now to FIG. 19, continuous electrical cable 600 is
manufactured by feeding multiple electrically conductive wires 602
into nip 604 formed by rotating mold roll 606 and counter-rotating
pressure roll 608. Wires 602 are bare, i.e., without an insulating
coating and are laterally spaced apart from one another as they
enter nip 604. In order to control the lateral position of the
wires as they enter the nip, guide rollers 616 are provided with
individual grooves, one for each wire introduced, to prevent the
wires from wandering laterally as they approach the nip.
Furthermore, pressure roll 608 has corresponding grooves that aid
in aligning wires 602 during the encapsulation process now to be
described.
[0131] Simultaneously with wires 602, a band 610 of molten
thermoplastic resin is introduced to nip 604 from extruder head
612. Pressure and temperature conditions in the nip cause the
molten resin to envelop the wires and also cause a portion of the
resin to fill hook shaped cavities 614 provided in mold roll 606.
As the cooled mold roll continues to rotate, the resin and
encapsulated wires remain adjacent the periphery of the mold roll
until take-off rollers 618 and 620 act to strip the product 600
from the mold roll, thus extracting the now solidified hooks 622
from their respective cavities 614.
[0132] Referring now to FIGS. 20 and 20A, product 600 has an
electrically insulating body 632 of thermoplastic resin with an
upper surface 624 and a lower surface 626. Loop-engageable hooks
622 extend from upper surface 624, each hook being an integral
extension of the thermoplastic resin of the insulating body. Hooks
622 have a stem portion 623 and a loop-engageable head portion 625
that extends outward from the stem to overhang upper surface 624.
Bottom surface 626 has peaks 628 corresponding to the wire guiding
grooves in pressure roll 608 with a valley 630 of reduced thickness
separating adjacent peaks 628. Each conductive wire 602 is
encapsulated within a peak 628 and separated from an adjacent
conductive wire by insulating thermoplastic resin body 632. In one
example, resin body 632 is of a flexible PVC material. The position
of wires 602 relative to upper surface 624 and lower surface 626 is
dictated by the relative positions of the wire and the molten
thermoplastic resin as they enter the nip and the flow dynamics of
the molten thermoplastic resin within the nip. As illustrated in
FIG. 19, by introducing the wires 602 above the extruder head 612
the tendency is for the wires to be relatively nearer upper surface
624 of final product 600 (as indicated by wires 602' shown as
dashed lines in FIG. 20). Conversely, if wires are fed from below
the extruder head (as indicated by wire feed 602A illustrated in
dashed lines in FIG. 19) the tendency is for the wires to be
relatively nearer lower surface 626 in final product 600 (as
indicated by wires 602'' shown as dashed lines in FIG. 20).
[0133] One alternative for controlling the vertical position of
wires 602 within insulating body 632 is to provide a supporting
substrate 633 beneath the wires as the molding process takes place.
As illustrated in FIG. 19, substrate 633 (shown as dashed lines) is
fed onto the grooved pressure roll 608 so that it sits on the peaks
of the grooves of the roll. Substrate 633 can be any material that
is conducive to supporting the wires while also allowing the molten
thermoplastic resin to flow through and encapsulate the substrate
during the molding process. In one example, substrate 633 is a mat
of nonwoven fibers. The wires 602A are then fed onto the substrate
at positions corresponding to the guiding grooves of pressure roll
608. The somewhat resilient substrate 633 allows wires 602A to
enter only partially into their respective guiding grooves of
pressure roll 608, thus allowing the lateral position of the wires
to be controlled while preventing the wires from reaching the
bottom of the grooves. Upon entering the nip, molten resin 610
flows upward to fill cavities 614 and downward through substrate
633 to fill the grooves of pressure roll 608, meanwhile the
substrate prevents wires 602A from sinking into contact with
pressure roll 608.
[0134] The resulting product 600' (FIG. 21) has the supporting
substrate 633 embedded beneath the wires 602 within the insulating
body 632.
[0135] In an alternative embodiment, also illustrated in FIG. 20
and further referring to FIGS. 22 and 22A, mold cavities 612 are of
a shape protruding straight inwardly from the periphery of mold
roll 606 toward its center, i.e., cavities 612 are shaped to form
stems only and do not have an undercut portion for forming an
engaging head of a fastener element. The rest of the cable forming
method proceeds as described above except the product 600'' (FIG.
22) stripped from the mold roll has only integrally molded stems
622' protruding from its upper surface 624'. Subsequent to the
stripping operation, the cable 600'' is passed between a heated
roller 634 and an anvil roller 636 (shown in dashed lines) to
produce a final product 600''' (FIG. 22A). Rollers 634, 636 are
arranged so that heated roller 634 contacts and deforms the tip
portion 623' of each stem 622' to form a loop-engageable head
portion 625' that overhangs upper surface 624'.
[0136] Referring now to FIGS. 23-25, another technique for avoiding
any potential problems of centering and/or fully encapsulating the
wires within the insulating body is to form the insulating body in
a two step process. Initially, an intermediate product 640 (FIG.
23) is formed by feeding wires 602 and band 610 of thermoplastic
resin into a nip formed by two pressure rolls 644 and 646. Similar
to the pressure roll 608 described above with reference to FIG. 20,
lower pressure roll 646 has peak and valley forming grooves on its
surface to aid in guiding the wires laterally, however, in this two
step process, upper pressure roll 644 has a flat peripheral surface
which forms the flat upper surface 648 (FIG. 24) of intermediate
product 640. Intermediate product 640 is then fed into a second nip
651 formed by a grooved lower pressure roll 650 and a mold roll 652
having hook cavities as described above. Simultaneously with
intermediate product 640, a band of thermoplastic resin 654 is
introduced from extruder head 653 to the nip directly adjacent the
periphery of the mold roll 652 and hooks 656 (FIG. 25) are formed
in a manner similar to that described above with reference to FIG.
20. The resulting final product 658 has a multi-layered structure
including an upper, hook bearing layer 660 permanently bonded
during the hook molding operation to a lower layer 662 that was
initially formed as intermediate product 640. Wires 602 are either
fully encapsulated by lower layer 662 or are fully encapsulated by
being sandwiched between the upper and lower layers 660, 662,
respectively.
[0137] Referring now to FIGS. 26 and 27, in yet another method for
forming a continuous cable with integrally molded fastener element
stems extending from a surface of a conductor insulating body, a
die 670 is positioned just upstream of nip 672. Die 670 includes a
wire guide plate 674 defining individual guide sleeves 676 each of
which receives and guides a conductive wire 678. Guide sleeves 676
can be cylindrically shaped for receiving wires of round
cross-section or can be of rectangular cross-section for receiving
flattened conductors to produce relatively flat cables. Arranged
perpendicular to the feed direction of the wires is an extruder 680
which introduces molten thermoplastic resin through nozzle 681 to
an internal resin flow path 683 defined by die 670. Flow path 680
directs the molten resin to flow above, below and between the
plurality of wires 678 before the combination 682 of wires and
molten resin is forced through slot 684 and into the immediately
adjacent nip 672. Once the material is in nip 672, the molding
process proceeds as described above with reference to FIG. 20 with
no further need for lateral or vertical wire guiding and/or
alignment.
[0138] In one particular embodiment, illustrated in FIGS. 28 and
29, the wires and thermoplastic resin are fed through a nip 700
formed by two mold rolls 702, 704, rotating in opposite directions.
Each mold roll 702, 704 defines an array of hook (or stem) forming
cavities 706, similar to those described above. In the embodiment
shown, two streams 708, 710 of molten thermoplastic resin are fed
into nip 700 while a plurality of laterally spaced apart conductive
wires 709, in the form of flat conductive strips, as illustrated,
are introduced to nip 700 between streams 708, 710. Alternatively,
streams 708, 710 are initially two solidified thermoplastic resin
films. The temperature and pressure conditions in the nip force the
thermoplastic resin (whether initially molten or solid) to at least
partially fill the cavities so that the solidified product 712
stripped from the exit side of the nip has loop-engageable fastener
elements 714 (or stems that can be later post-formed as described
above) protruding from opposite broad surfaces 716, 718 of the
electrically insulating body 720 of thermoplastic resin.
[0139] Yet another method for producing electrical cables of the
present invention is illustrated in FIGS. 30-33. The method is a
lamination process in which a pre-formed hook tape 730, spaced
apart electrical conductors 732 and a backing tape 734 are
simultaneously fed between two bonding rollers 736, 738. Pre-formed
hook tape 730 is of an electrically insulating thermoplastic resin,
one example being a polyester material, hook tape 730 having a base
740 defining first and second surfaces 742, 744, respectively.
Hooks 746 are protrusions of the thermoplastic resin of first
surface 742 and are suitable for engaging a loop material. Hook
tape 730 is fed between pressure rolls 736 and 738 with its
hook-bearing first surface 742 immediately adjacent the peripheral
surface of the first pressure roll 736. Backing tape 734, also of
an electrically insulative material (but not necessarily of the
same material as hook tape 730), defines a first surface 748 and a
second surface 750 and is fed between rolls 736 and 738 with its
first surface 748 immediately adjacent the peripheral surface of
pressure roll 738.
[0140] Simultaneously with hook tape 730 and backing tape 734, a
plurality of flat conductive strips (or wires of circular
cross-section) is introduced between pressure rolls 736, 738 in
laterally spaced apart fashion. Conductors 732 are positioned
between second surface 744 of hook tape 730 and second surface 750
of backing tape 734. Pressure roll 736 has a series of protruding
rings 752 arranged to contact first surface 742 of hook tape 732
only along regions 753 of the forming laminate 754 that lie between
the spaced-apart conductors 732. Rolls 736 and 738 are heated and
positioned to create pressure in the regions 753 corresponding to
each ring 752 such that thermal bonding occurs along the contacted
regions of laminate 754. The thermal bonding lines act to
permanently weld hook tape 730 to backing tape 734 in a manner that
electrically isolates conductors 732 from one another and insulates
the conductors between the hook tape and the backing tape.
Pre-formed hook tape 734 can be provided with regions 753
distinguished by flat areas (as illustrated in FIG. 31) on first
surface 742, i.e., areas lacking rows of hooks 746. Alternatively,
first surface 742 of pre-formed hook tape can have a uniform array
of hooks 746 across its surface, the hooks in regions 753
subsequently coming into contact with rings 753 whereby the hooks
are melted and or crushed by the applied pressure and heat. Either
way, the hooks remaining on surface 742, i.e., those positioned
between rings 752 during the lamination process, are sufficient to
provide the necessary fastening capability with mating loop
materials.
[0141] In another alternative, pressure roll 736 acts as an anvil
(rotary or stationary) while pressure roll 734 is ultrasonically
vibrated at a frequency which causes hook tape 730 to be welded to
backing tape 734 along the regions 753 where rings 752 contact hook
tape 730.
[0142] Referring again to FIG. 30 and now also to FIG. 34,
electrical cable 800 is made by yet another laminating method. Hook
tape 730 (as described above with reference to FIGS. 30 and 31) is
provided with a layer of electrically insulating adhesive 770
(shown as dashed lines in FIG. 30) applied to its second surface
744 as it is fed between smooth pressure rolls 760 and 762.
Similarly, backing tape 734 is provided with a layer of adhesive
771 (dashed lines) applied to its second surface 750 as it is fed
between rolls 736, 738. However, unlike the methods discussed
above, in this particular example rolls 736 and 738 both have a
smoother outer surface, i.e., neither roll has the pressure rings
752 discussed above with reference to FIG. 33. Conductors 732 are
introduced between the rolls so as to be sandwiched between the
hook tape and the backing tape. The smooth pressure rolls are
arranged to cause the adhesive 770 on second surface 744 of hook
tape 730 and the adhesive 771 on second surface 750 of backing tape
734 to contact one another, thereby bonding the two tapes together.
The adhesive also contacts the conductors 732, at least partially
encompassing them and acting in combination with the hook tape
and/or the backing tape to envelop and electrically isolate the
conductors from one another. It is also possible to eliminate one
of the adhesive layers 771, 772, the remaining adhesive layer being
sufficient to bond hook tape 730 to backing layer 734 while
enveloping and electrically isolating conductors 734 between the
layers.
[0143] In yet another alternative, the backing tape 734 is in the
form of a second strip of hook tape, similar or identical to the
hook tape 730 described above, so that the resulting electrically
conductive cable has loop engageable hooks extending from opposite
exposed surfaces.
[0144] It should be noted that in the adhesive laminating examples
just discussed, the hooks 746 are not permanently deformed to any
significant extent by their passage through the smooth pressure
rollers. Rather the hooks are resilient enough to withstand the
pressures applied by the unheated rolls.
[0145] As illustrated in FIG. 35, hook fastener tape 810 has hook
fastener elements 814 extending from a first 812 of two, opposite
broad surfaces 812, 813 of base 816. While the illustrated hook
fastener elements 814 of FIG. 35 are truly hook-shaped, the phrase
"hook fastener elements", as used herein, refers generically to
protrusions having tips shaped for engagement with a complementary
loop material or, alternatively, with other like or unlike
complementary protrusions. Each hook fastener element 814 has an
engaging head 818 capable of releasably engaging a mating fastener
material, e.g., loop material. Examples of other appropriate hook
fastener element shapes include, but are not limited to stems
having mushroom-, flat-headed disc- and palm tree-shaped heads.
[0146] Again, as discussed above with reference to FIG. 5, an
example of a commercially available hook fastener tape suitable for
use in the invention is the hook product designated CFM-29
available from Velcro USA, Corp. of Manchester N.H. The CFM-29 hook
product has hooks of 0.015 inch (0.38 mm) height, a base thickness
of 0.003 inch and a hook fastener element density of the order of
1000 or more hook fasteners per square inch.
[0147] Fastener tape 810 can be advantageously produced
continuously and integrally of thermoplastic resin as described
above, again with reference to U.S. Pat. No. 4,794,028, issued Dec.
27, 1988, to Fischer. Briefly, as illustrated, the right-hand
portion of 1004 in FIG. 2, the Fischer process employs a nip formed
between a mold roll 1006 and a pressure roll 1008. Molten
thermoplastic resin 1000 is fed into nip 1004 while the mold and
pressure rolls rotate in opposite directions, as indicated by the
arrows in FIG. 36. Pressure in the nip forces extruded resin, to
fill a plurality of hook-fastener-shaped cavities (1010) provided
in mold roll 1006. Resin in excess of cavity volume takes the shape
of the nip to form the base substrate, e.g., (base 816 of FIG. 35).
Subsequently, the resin solidifies and is stripped from the mold
roll to produce continuous fastener tape 810.
[0148] Other techniques for continuously and integrally forming a
thermoplastic hook fastener tape are equally suitable for use with
the present invention. One such technique involves the extrusion of
thermoplastic resin into a gap formed between the extrusion head
and the mold roll without the use of a separate pressure roll. This
technique is more fully described, for example, in U.S. Pat. No.
5,441,687, issued Aug. 15, 1999, to Murasaki et. al, to which the
reader is referred for further information.
[0149] In another suitable technique, stems rather than hook
fastener element shaped projections are initially formed integrally
with a thermoplastic base. Subsequently, the tops of the stems are
shaped to form engaging heads by, e.g., contacting the stem tips
with a heated roller or heating the stem tips contacting them with
an unheated or cooled roller, to produce stems having heads capable
of engaging complementary loops or like or unlike shaped hook
fastener elements. Examples of these techniques are more fully
illustrated in U.S. Pat. No. 5,077,870 issued Jan. 7, 1992 to
Melbye et al. and U.S. Ser. No. 09/231,124, filed Jan. 15, 1999,
respectively. The reader is referred to both of these references
for further information.
[0150] In yet another suitable technique, a thermoplastic base is
extruded having continuous rails of hook fastener-shaped profile.
The rails, but not the base, are subsequently slit laterally at
intervals along the length of the extrusion to form separate
portions of the fastener-shaped rail, each portion separated from
an adjacent portion by a slit. The base is then permanently
stretched longitudinally to create space between adjacent portions
of the fastener-shaped rails. The resulting fastener tape has rows
of spaced individual hook fastener elements. Such a technique is
more fully described for example, in U.S. Pat. No. 4,894,060,
issued Jan. 16, 1990, to Nestegard, to which the reader is referred
for further information.
[0151] As illustrated in FIG. 35A, fastener tape 910 has a
relatively thin layer 902 of electrically conductive material
disposed on its hook fastener element-bearing surface 912. The
electrically conductive material forms a layer of roughly uniform
thickness that follows closely the contour of fastener tape 910.
Preferably, the coating material is highly conductive, e.g.,
silver, the thin layer of the material offering low resistance to
the transmission of electrical signals along the fastener tape.
Also, it is preferable that the conductive coating 902 be attached
to the fastener tape 910 in a manner that allows the fastener tape
to remain flexible. Where the conductive coating encompasses hook
fastener elements, it is important that the conductive coating
allow the hook fastener elements to flex as necessary to engage and
disengage complementary loop or other hook fastener elements while
remaining integral with the fastener tape.
[0152] Referring again to FIG. 36, a technique for applying an
electrically conductive layer 902 to fastener tape 910 to produce a
conductive hook tape having the preferred properties previously
described is illustrated. The method includes a reduction process
in which the conductive material reacts with a previously applied
sensitizer to attach the conductive material to fastener tape 910.
In one example, referred to herein as "silvering" and now to be
described, the sensitizer comprises tin and the electrically
conductive material comprises silver. The silvering process is a
chemical reaction that results when a solution of silver salt comes
in contact with a reducer. The silver deposits where the surface
has been treated with a sensitizer which coats the surface with a
thin layer, e.g., a thickness of the order of the molecular size of
the sensitizer compound, of tin on which the silver attaches.
[0153] As illustrated in FIG. 36, molten resin 1000 is extruded
from extruder head 1002 into a nip 1004 formed between a mold roll
1006 and a pressure roll 1008. Mold roll 1006 has a plurality of
hook-shaped cavities 1010 formed to extend inwardly from its
nip-forming surface. Pressure created in the nip forces molten
resin 1000 to enter cavities 1010 while excess resin remains in the
nip between the mold and pressure rolls. As the rolls rotate (in
the direction indicated by the respective arrows) the resin remains
associated with the mold roll as it cools and begins to solidify.
The resin in the cavities forms hook fastener elements (e.g., hook
fastener elements 814 of FIG. 35) and the resin that remains
associated with the peripheral surface of mold roll 1006 forms a
base (e.g., base 816 of FIG. 35) from which the hook fastener
elements extend. The resulting fastener tape 1020 is stripped from
mold roll 1006 by stripping rolls 1022 and 1024 is then passed on
to the "silvering" stage where the conductive material is
applied.
[0154] In some cases, in order to prepare the surface to be
conductively coated, a wetting agent is first applied at station
1030. In one example the thermoplastic resin of the fastener tape
is polypropylene, and the wetting agent is a product known as C22
and available from Peacock Laboratories Inc., of Philadelphia, Pa.
The C22 is mixed with water (preferably deionized) in a ratio of 14
ml. to 16 oz., respectively, and is then sprayed, as illustrated by
sprayer 1032, dipped, or wiped onto the desired area of the hook
fastener product.
[0155] With the wetting agent applied, the hook fastener product is
then passed on to station 1040 where a sensitizing solution is
applied. Again using the example of a polypropylene thermoplastic
resin, one appropriate sensitizing solution is No. 93 Sensitizing
Solution available from Peacock Laboratories Inc., of Philadelphia,
Pa. The No. 93 Sensitizing Solution is mixed with water (preferably
deionized) in a ratio of 14 ml. to 16 oz., respectively, and is
then sprayed, as illustrated by sprayer 1042, dipped, or wiped onto
the desired area of the hook fastener product.
[0156] After allowing the sensitizing solution to cure on the hook
fastener product, e.g., approximately 60 seconds in the case of No.
93 Sensitizing Solution on polypropylene, the hook fastener product
is directed to station 1050 where the treated areas are rinsed with
water (preferably deionized). Rinsing is effectively accomplished
by spraying, as illustrated by sprayer 1052, dipping, or wiping the
desired area with the rinse water.
[0157] The hook fastener product is then directed to station 1060
where it is saturated with a silvering solution to apply the
electrically conductive coating. In the case of a hook fastener
product of polypropylene, an appropriate silvering solution is
HE-300 available from Peacock Laboratories Inc., of Philadelphia,
Pa. The HE-300 silvering solution is made up of three constituent
solutions including HE-300 Silver Solution "A", HE-300 Activator
Solution "B" and HE-300 Reducer solution "C". All three components
of the silvering solution are applied simultaneously by a
dual-nozzle spray gun 1062. A first nozzle 1064 of spray gun 1062
is supplied from a tank containing the following mixture: Equal
amounts of HE-300 Silver Solution "A" and HE-300 Activator Solution
"B" each mixed with water (preferably deionized) in a ratio of 14
ml. to 8 oz., respectively. To avoid a potentially explosive
reaction in the mixing tank, it is preferable to mix each of the
concentrated HE-300 "A" and "B" solutions with the water, as
opposed to mixing the concentrated solutions directly together.
[0158] Simultaneously, with the spraying from the first nozzle
1024, second nozzle 1066 sprays a solution supplied from a supply
tank in which HE-300 Silver Reducer has been mixed with water
(preferably deionized) in a ratio of 14 ml. to 16 oz.
[0159] The dual nozzle spray gun 1062 operates to simultaneously
spray equal amounts of the mixtures from both spray nozzles 1064,
1066. As illustrated, nozzles 1064 and 1066 are biased toward each
other so that their respective outputs mix at approximately their
point of contact with hook fastener product. The result is that the
separate streams combine approximately as the streams contact the
surface of the hook fastener product. The area to be coated is
saturated with the spray from dual nozzle spray gun 1062 until the
surface changes to a gray/gold color. At this point, the conductive
coating is sufficiently complete.
[0160] In another embodiment, the formed hook fastener product is
covered by a masking material prior to the silvering process. As
illustrated in FIG. 2, optional masking station 1070 (indicated by
dashed lines) can provide a film that blocks the subsequent
coatings applied at stations 1030, 1040, 1050 and 1060. When the
film is patterned so as to allow passage of the subsequent coatings
in only selected areas, the result is a hook fastener product that
has a layer of conductive material applied to only an area
corresponding to the pattern. The masking film can be subsequently
removed leaving a conductive pattern disposed on an otherwise
non-conductive surface.
[0161] In yet another embodiment, a piercing station 1080 is
provided in which the formed hook fastener tape is pierced, e.g.,
by stakes 1082, to form through-holes that extend from a first to a
second broad surface of the fastener tape base. Subsequent
silvering of the hook fastener tape coats the surfaces defining the
through-holes with conductive material. These conductive
through-hole surfaces provide passageways for electrical signals to
be passed from a first to a second surface of the hook fastener
tape.
[0162] In one example, illustrated in FIGS. 37A-37E, formed hook
tape 1100 (FIG. 37A) is initially provided as a continuous sheet of
thermoplastic resin 1102 having opposite, first and second broad
surfaces 1101, 1103 with an array of integrally formed hook
fastener elements 1104 extending from first broad surface 1101. As
illustrated in FIG. 37B, hook tape 1100 is pierced to provide
through-holes 1112 at various predetermined locations along the
tape. Subsequently, a masking film 1120 (FIG. 37C) having a pattern
of openings 1122 formed on an otherwise solid surface 1124 is
applied (FIG. 37D) to the pierced hook tape. The location and
frequency of the piercing that forms the through-holes of pierced
hook tape 1100 and the pattern of openings 1122 on masking film
1120 are selected so that the application of masking film 1120 to
pierced hook tape 1110 results in masked hook tape 1130 (FIG. 37D)
having at least one through-hole 1112 disposed within at least one
opening 1122, and in some embodiments, within each opening 1122.
Masked hook tape 1130 is then coated with the conductive material,
e.g., as described above, and the mask is removed to produce a
selectively conductive hook fastener product 1140 having selected
regions that are electrically conductive. The conductive areas 1142
correspond to the openings 1122 of masking film 1120 and each
conductive area 1142 has at least one through-hole 1112, the
defining surfaces 1144 of which are also conductively coated. The
coated through-hole surfaces provide for the transmission of
electrical signals from the hook fastener element bearing side of
the hook tape to the opposite side.
[0163] The process described above with reference to FIGS. 36 and
37A-37E, can be advantageously employed to produce a wide variety
of electrically conductive fastener products. In one example, a
hook fastener cable 1200, extending between opposite longitudinal
ends 1221 and 1223, as illustrated in FIGS. 38A and 38B is
produced. The cable is formed of a substrate 1201 having two broad,
opposite surfaces 1204, 1206 with hook fastener elements 1202
extending from broad surface 1204. Hook fastener elements 1202 and
broad surface 1204 can be formed integrally from a thermoplastic
resin, e.g., polypropylene, employing the process described above
with reference to FIG. 36. Continuous conductive bands 1208 are
applied to surface 1204 and extend along the length of the cable.
The bands are separated from each other, e.g., by applying
appropriate masking film strips to cable surface 1202 similar to
the process described above with respect to FIG. 36. Such a cable
can be produced in continuous length and subsequently cut to a
desired length for its intended use.
[0164] Cable 1200 has electrical connectors 1222 at its terminal
longitudinal ends. Conductive bands 1208 allow for passage of
electrical signals between the two terminal connectors 1222 while
hook fastener elements 1206 allow the cable to be releasably
secured to a surface (not shown) equipped with complementary
fastening material, e.g., a loop material. Also, as illustrated in
FIG. 38A, an electrical signal processing component 1230, e.g., a
microchip or circuit board having filters, diodes, etc., is
equipped with one or more patches of a complementary fastening
material 1232 releasably engageable by hook fastening elements
1202. Electrical component 1230 can be releasably fastened at a
selected position along the length of cable 1220 as indicated by
attached electrical component 1230' shown in dashed line in a
secured position on cable 1220. In some cases, the conductive bands
1208 are positioned to encompass some of the hook fastener elements
1202 of cable 1220, and where the electrical signal processing
component 1230 is equipped with electrically conductive
complementary fastening material, e.g., metallized loop material,
an electrical signal can be transmitted between band 1208 of cable
1220 and electrical signal processing component 1230 by way of the
releasably engaged complementary fastener elements 1202 and
1232.
[0165] In the example illustrated in FIGS. 39A-39C, cable 1300 has
hook fastener elements 1302 integrally formed and extending from
broad surface 1304. Discrete strips 1308 of electrically conductive
material are attached to and extend in continuous fashion along an
opposite broad surface 1306 of cable 1300. Cable 1300 can be
produced by the process described above with reference to FIG. 36
by manipulating the extruded, molded thermoplastic web so that its
surface opposite the hook fastener elements is exposed to the
conductive material application process. Use of an appropriately
shaped mask allows the conductive material to be attached to the
thermoplastic substrate as discrete strips 1308.
[0166] In the example illustrated in FIGS. 40A-40B, cable 1400 has
discontinuous strips 1408 of electrically conductive material
attached to a broad surface 1406 opposite the hook fastener element
bearing surface 1404. The discontinuities 1410 can be of
pre-determined dimension, e.g., by appropriate mask design when
cable 1400 is produced by the process illustrated in FIG. 36, so
that electrical components 1420 can be subsequently attached, e.g.
by soldering welds 1422, to bridge the discontinuity. The resulting
hook fastener cable 1400 becomes a flexible carrier of one or more
electrical components 1420 (i.e., cable 1400 is a flexible circuit
board) and cable 1400 can be releasably secured to any surface
having complementary loop or other hook fastener elements that are
engageable with hook fasteners 1402.
[0167] As illustrated in FIG. 41, various other patterns of
electrically conductive tracks can be formed on the surface 1506 of
a hook fastener cable 1500 so that electrical components 1520 can
be attached to process and or modify electrical signals that pass
through the cable. Again, the desired pattern of electrical
conductive material can be attached by use of an appropriate mask
design to form flexible circuit board 700.
[0168] Furthermore, the flexible circuits 1400 and 1500 of FIGS.
40A, 40B and 41 can be initially formed by any circuit forming
method and without integral fasteners extending therefrom. The
circuits (e.g., conductive paths 1409, 1509) can be on an exposed
surface of a substrate (as shown) or can be embedded, e.g.,
electrically insulated, within a substrate 1401, 1501. Such
flexible circuits can then be processed using one or more of the
techniques described above to laminate a pre-formed hook or loop
fastener element-bearing tape thereto or to simultaneously form and
laminate thereto a hook element-bearing fastener tape. Also, if
desired, the hook tape can be laminated and/or formed to
simultaneously electrically insulate a previously exposed
conductive path. Either prior to feeding the flexible circuit
through the laminating/forming gap or after, insulating material
can be removed (e.g., by the hole punching technique described
above or by any other method) to expose portions of the conductive
path 1409, 1509 for electrical connection to other electrical
conduits and/or devices.
[0169] Referring now also to FIGS. 41A, 41B and 41C, a second
substrate 1530, e.g., a polyester film, is provided. Film 1530
defines a first 1534 and a second 1536, opposite broad surface and
can be a flat substrate, or alternatively, can have integrally
formed hook fastener elements 1532 (illustrated by dashed lines and
formed as described above) protruding from first surface 1532. Film
1530 can be laminated to any of conductive path bearing substrates
1300, 1400 or 1500 in such a manner that the conductive path is
disposed between the conductive path bearing surface, e.g., 1306,
1406, 1506 of substrate 1300, 1400, 1500 and the second surface
1536 of film 1530 thus producing flexible circuit product 1550
(FIG. 41C). Lamination of film 1530 over conductive path 1308,
1409, 1509, can be accomplished by any method, e.g., tradition
methods such as adhesive 1538 (shown in dashed lines), thermal or
ultrasonic bonding, and/or any other laminating technique including
any described above.
[0170] In a particularly advantageous embodiment, portions 1540 of
film 1530 are removed, e.g., by punching or piercing, at desired
locations so that after lamination, portions 1542 of conductive
path 1308, 1409, 1509 are accessible for, e.g., electrical
connection(s). When adhesive is used in the lamination process, it
is desirable that the adhesive 1538 be applied to surface 1536 of
film 1530 prior to the removal, e.g., punching and/or piercing,
process so that after lamination the adhesive does not interfere
with electrical connection(s) to the exposed portions 1540 of
conductive path 1308, 1409, 1509.
[0171] As illustrated particularly in FIG. 41D, when film 1530 has
hook fastener elements 1532 extending from first surface 1534 and
conductive path bearing substrate 1300, 1400, 1500 likewise has
hook fastener elements 1302, 1402 extending from its exposed
surface 1304, 1404, 1504 the resulting laminate is a double sided
hook bearing flexible circuit 1550. This is particularly
advantageous because it allows for flat securement of the flexible
circuit in an area requiring that the path of circuit securement
change drastically, e.g., a 90.degree. turn. This is accomplished
by initially fastening hook fastener elements 1302, 1402 of
substrate 1300, 1400, 1500 to mating elements (e.g., exposed loops)
of a supporting surface 1554 and then folding the circuit upon
itself (as illustrated at 1552) and attaching the hook fastener
elements 1532 of film 1530 to supporting surface 1554 (or another
supporting surface).
[0172] In one embodiment, illustrated in FIG. 42, a fastener
product 1600 has a first surface 1602 with conductive coated hook
fastener elements 1604 and an opposite second surface 1606 with
conductive loop material 1608. Such a "back-to-back" conductive
fastener product can be produced by a modification to the process
described above with reference to FIG. 36. As indicated in dashed
lines, a conductive loop material 1610 is fed from a roll 1612 into
nip 1004 simultaneously with extruded resin 1000. An outer surface
of loop material contacts pressure roll 1008 and an inner surface
contacts molten resin 1000 as the resin is forced into hook-forming
cavities 1010 of mold roll 1006. Pressure in the nips causes the
inner surface of the loop material and the resin to become
permanently bonded as the hooks are molded. Such a process and
variations thereof are more fully described, for example, in U.S.
Pat. No. 5,260,015 to Kennedy et al., issued Nov. 9, 1993, to which
the reader is referred for further information.
[0173] One example of a conductive loop material 1610 suitable for
use in producing back-to-back conductive fastener 1600 is a product
marketed under the tradename HI-MEG BRAND Loop tape and available
from Velcro U.S.A. Corp., Manchester, N.H. The conductive nature of
at least the outer surface of loop material 1610 remains
substantially unaffected by the temperatures of the molding process
because the pressure roll is typically either unheated or cooled.
Alternatively, loop material 1610 may be initially a noncoated,
nonconductive loop material that is fed into nip 1004, and
subsequently both the hook and loop surfaces of the resulting
product can be conductively coated in a post-forming operation.
[0174] A number of embodiments of the invention have been
described. Nevertheless, it will be understood that various
modifications may be made without departing from the spirit and
scope of the invention. For example, as an alternative to the
masking process described above for producing a desired pattern of
electrically conductive material on a hook fastener substrate, a
removal process can be employed. Such a removal process can be
implemented by first providing a hook fastener tape having one or
both broad surfaces coated with a conductive layer as described
above with reference to FIGS. 2 and 3 and subsequently removing
selected portions of the conductive coating to leave a desired
conductive pattern on the substrate. Removal can be achieved by,
e.g., machining, grinding, or cutting the conductive material to
remove it from the desired areas. Of course, electrical components
(e.g., 1420 and 1520 as described above) can then be soldered or
otherwise electrically connected in desired areas on the
substrate.
[0175] Furthermore, and quite notably, many of the above described
techniques can be combined to produce fasteners having combinations
of the various described features as desired for the particular
application of the resulting electricity conducting fastener. For
example, the circuit printing techniques and resulting products
described with reference to FIGS. 36-41 can be combined with the
techniques described with reference to FIGS. 9, 13, 19, 23 or 28.
The result is to form a printed or otherwise deposited circuit
pattern on a substrate (possibly a substrate already bearing
fastener elements on an exposed surface opposite the circuit
pattern), and to then form hook fastener elements, e.g., hooks,
while simultaneously covering and insulating the otherwise exposed
circuit pattern. The resulting product can have, for example, hooks
on one or both major exposed surface, or hooks on one major exposed
surface with loops on the opposite major exposed surface. Also, the
piercing techniques described with reference to FIGS. 37A-37D can
be employed to provide exposed areas of the otherwise insulated
circuit pattern for, e.g., connecting power supply or other
terminals and connections. Accordingly, other embodiments are
within the scope of the following claims.
[0176] A number of embodiments of the invention have been
described. Nevertheless, it will be understood that various
modifications may be made without departing from the spirit and
scope of the invention. Accordingly, other embodiments are within
the scope of the following claims.
[0177] The entire contents of each of the references to which the
reader has been referred to for further information above are
hereby fully incorporated by reference.
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