Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BACKGROUND OF THE INVENT ON
~ield of the Invention:
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The present invention relates generally to surface type
fasteners known as hook-and-loop fasteners~ and more particularly
to a fabric fastener tape carrying on its one surface a number
of hook-shaped material engaging elemen~s and a method of pro-
ducing ~uch a hooked fabric fastener tape.
Prior Art:
According to a known method, a hooked fabric fastener
tape of the type described is produced from a terry or uncut
pile fabric carrying on its one surface a number of loops raised
~rom the one surface, each o the loops havins a pair of spaced
leg sections and a head section interconnecting the leg sections.
Each loop is cut open or severed at one of the leg sec~ions
thereof to produce, on one hand, a hook-shaped material engaging
element and, on the other hand, a stem. The prior art hooked
fabric fastener tape is disadvantageous in that after the loops
ha~e been cut open, the stems remain on the fastener tape
adjacent to the corresponding hook shaped material engaging
elements in confrontin~ relation tb orsubstantially in vertical
alignment with the respecti~e free ends thereof. The stems are
liable to hinder cooperating loops on a mating looped fabric
fastener tape from being introduced into and hooked by the
hook-shaped material engaging elements as the two fastener tapes
are pressed into face-to-face contact together. As a result,
the possibility of hooking between hooks and loops, and hence
the ~irmness of engagement of a hook-and-loop fastener is
considerably decreased. In order to displace the hook-shaped
material engaging elements away from the stems, the prior art
method requires an additional treatment by a raising
machine or another complicate and expensive device.
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It is an object ofthe invention to provide a hooked
fabric fastener tape for hook-and-loop fasteners which can
adhere to or ~ngage with a cooperating looped fabrlc fastener
tape with an increased degree of firmness.
Another o~ject of the invention is to provîde a hooked
fabric fastener tape having hook-shaped material engaging
elements which can hook cooperating loops of a mating looped
fa~ric fastener reliably without causing mis-en~a~e~ent therewith.
A further object of the invention is to provide a method
which produces such a hooked fabxic fastener tape simply and
less costly.
SUMMARY OF THE INVENTION
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A hookad fa~ric fastener tape has on one of opposite
surfaces of a foundat;on structure a num~er of hook shaped
material engaging elements and stems which have been produced
in pair from loops on the foundation structure. The respective
free ends o~ the hook-shaped material engaging elements and the
stems are displaced angularly away i-rom one another as viewed
fxom the general plane of the foundation structure for easy
hooking engagement with cooperating loops of a mating looped
fabric fastener tape.
According to a method of the present invention, a plurali-
ty of warp threads of synthetic resin material are woven, while
being exerted thereon a torque, together with a plurality of
foundation weft and warp threads so as to form loops with the
synthetic resin warp threads raised from the so woven foundation
structure, each of the loop having a pair of leg sections and
a head section interconnecting the legs. The loops are heated
at a temperature which causes the loops to retain their shape
to form raised pile th~eads while allowing the loops to retain
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~n internal torsional stress stored during the weaving operation.
Upon cutting the loops at respective ones of the legs, hook-
shaped material engaging elements and stems produced from the
respective loops are allowed to displace, due to the internal
torsional stress stored therein, angularly away from one another
as viewed from the general plane of the foundation structure.
The abo~e and other objects, advantages and features of
the present invention will become apparent from the followi`ng
description of a pre~erred embodiment taken in conjunction with
the accompanying drawings, in which:
BRIEF DESCRIPTION OF . THE DRAWINGS
FIG. 1 is a fra~mentary diagrammatic front elevational
view of loops on a foundation structure befoxe being converted
into a hooked fabric fastener tape according to the invention;
FIG. 2 is a side elevational view of FIG. 1;
FIGS. 3 and 4 are views similar ~o FIG5. 1 and 2, respec-
ti~ely, showing a hooked fa~ric fastener tape having on one of
opposîte surfaces of a foundation structure a plurality of
hook-shaped material engaging elements and stems which have
~een produced ~y cutting the loops at respective one leg sections
thereof shown in FIGS. 1 and 2, according to the present inven-
tion; and
FIG. 5 is a plan view o~ FIG. 3.
DETAILED DESCRIPTION OF T~E PREFERRED EMBODIMENT
~ eferring now to the drawing, wherein like reference
characters designate identical or corresponding parts throughout
the several views, and more particularly to FIGS. 1 and 2, there
is shown an uncut pile or looped fabric fastener tape 10 produced
in accordance with the present invention. The looped fabric
fastener tape 10 încludes a foundation structure 11 constituted
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by a weft thread and a plurality of first warp thr~ads woven
with the weft thread (these threads being not shown for clarifi- I
cation).
The fastener tape 10 also includes on one o~ opposite
surfaces of the foundation structure 11 a number of loops 12
formed with a plurality of second warp threads woven into the
foundation structure during the weaving operation of the same
in a loom of the general type employed in weaving vel~et ribbon.
Each of the loops 12 has a pair of leg sections 18,19 and
a head section 20 interconnectins the leg sections 18,19. The
second warp threads preferably are thermoplastic monofilaments
made of a synthetic resin material, such as nylon or Gther
material capable of being set by heat into a predetermined shape.
The second warp threads are woven, while exerting
thereon a torque or torsional load, together with the foundation
weft and warp threads, with the result that the loops 12 formed
with thus twisted warp threads are twisted correspondingly as
shown in FIG~ 20 Exertion of the ~orque or twist may be done
either as the second warp threads a:re supplied into the loom
for formation of the loops 12 or as they are wound on bobbins,
with the a~d of a suitable torque excertion means.
q`he loops 12 are heated at a temperature which causes
the loops 12 to retain their shape to form raised pile threads
~hile allowing the same to retain an internal torsional stresses
stored during the weaving operation. Th~ heating temperature
of the loops 12 is preferably set at a relatively low temperature
in a ranye wi~hin which the second warp threads of thermoplastic
synthetic resin material have the thermoplasticity.
Each of the loops 12 is then cut open or severed at one 18
of the respective leg sections 18,19 to produce, on one hand,
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a hook-shaped material engaging element 13 formed jointly with
the other leg section 19~ the head section 20 and a part of the
one leg section 18 and, on the other hand, a stem 14 formed with
the reminder of the cut one leg section 18 and constituting
a dressed nap, whereupon the hook-shaped material engaging
element and the stem 13,14 are allowed to displace, due to the
internal torsional stress stored therein, angularly away from
each other as viewed from the general plane of the foundation
structure 11, as shown in FIGS. 3 to 5. Thus, a large opening
is provided between the free end of the hook-shaped element 13
and the stem 14 for easy reception of a corresponding loop 16 on
a mating looped fabric fastener tape 17 (shown by phantom lines
in FIG.`3). A hooked fabric fastener tape 15 now converted from
the looped fabric fastener tape lO has the hook-shaped material
engaging elements 13 which allow the cooperating loops 16 on the
looped fabric fastener tape 17 to enter into hooking engagement
therewith smoothly and reliably as the two fastener taFes 15,17 are
pressed together. As a result, the possibility of hooking betwee
hooks and loops, i.e. the firmness of engagement of a fastener
is substantially increased.
Following to the loop-heating operation and prior to the
loop-cutting operation, the~fastener tape 10 may be subjected
to additional treatments at the desire, such as dyeing and
fixing of the loops 12 to the foundation structure ll. The
latter operation may be effected by coating or impregnating on
the other or reverse surface of the foundation structure 11
with an adhesive or a heat settable resin capable of withstand-
ing such temperatures as are likely to be encountered in normal
usage of a hook-and-loop fastener of which the hooked fabric
fastener tape 15 forms a part.
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Although various minor modifications may be suggested by
those versed in the art, it should be understood that I wish
to embody within the scope of the patent warranted hereon, all
such embodiments as reasonably and properly come within the
scope of my contribution to the art.
