U.S. patent number 3,778,870 [Application Number 05/213,464] was granted by the patent office on 1973-12-18 for statistical hook and loop area fasteners.
This patent grant is currently assigned to Mattern, Ware and Dairs. Invention is credited to Robert A. Bennett.
United States Patent |
3,778,870 |
Bennett |
December 18, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
STATISTICAL HOOK AND LOOP AREA FASTENERS
Abstract
A separable hook-and-loop area fastener incorporates a loop pile
sheet and a facing hook sheet presenting multiple-sawtooth hooks.
The hook sheet of the fastener is formed by weaving, looping or
otherwise engaging with a backing sheet a continuous plastic
filament, preferably of nylon or the like, which has been
permanently crimped into a zig-zagged sawtooth configuration by
passing the same between a pair of oppositely sawtoothed forming
rolls. The continuous plastic filament loops are preferably formed
in a plurality of aligned rows so that a plurality of loops may be
engaged by a common elongated knife edge and simultaneously cut.
The loops preferably are large enough and the sawtooth formations
small enough so that a plurality of sawteeth are provided in each
loop. When cut, the zig-zag sawtooth monofilaments stand up
perpendicular to the sheet support, and are provided with a
plurality of hook-like formations. The loop pile sheet for
engagement with the hook sheet may be conventional.
Inventors: |
Bennett; Robert A. (Shelton,
CT) |
Assignee: |
Mattern, Ware and Dairs
(Bridgeport, CT)
|
Family
ID: |
27395870 |
Appl.
No.: |
05/213,464 |
Filed: |
December 29, 1971 |
Current U.S.
Class: |
24/449 |
Current CPC
Class: |
A44B
18/0015 (20130101); Y10T 24/2767 (20150115) |
Current International
Class: |
A44B
18/00 (20060101); A44b 017/00 (); A44b
013/00 () |
Field of
Search: |
;24/204
;85/14,28,49 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gelak; Bernard A.
Claims
What is claimed is:
1. A multiple hook-bearing sheet for a statistical hook and loop
area fastener comprising:
A. a backing member; and
B. a plurality of hook elements each formed of a relatively stiff
shape retaining filament,
a. each said hook element having one end embedded in said backing
member and the other end free, and
b. each said hook element comprising at least one zig-zag shaped
hook portion comprising a relatively straight portion of said
filament upstanding away from said backing member, a relatively
straight return portion of said filament formed at an acute angle
therewith and an upstanding relatively straight portion of said
filament formed at a second acute angle with said return
portion.
2. The hook elements defined in claim 1 wherein each of said hook
elements comprises at least a pair of hook portions.
3. The hook elements defined in claim 1 wherein said hook elements
are planar.
4. The hook elements defined in claim 1 wherein each of said hook
elements comprises one leg of a U-shaped continuous hook-forming
loop-embedded in said backing member, the free ends of the legs of
the adjacent U-shaped elements being the matching cut ends of a
continuous filament.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to statistical hook and loop area fasteners.
Particularly it relates to such separable fasteners of the kind
currently sold in the United States under the trademark
"VELCRO."
2. Prior Art
Such fasteners comprise two usually all nylon sheets or tapes, one
covered with a myriad of finely woven monofilaments formed in the
permanent hooks, the other covered with soft nylon loops. When
pressed together, they intermesh together and fasten tigntly in a
random or "statistical" fashion, yet they can be readily peeled
apart. These prior art fasteners, which have been commercially
successful, are formed by weaving a monofilament in and out of a
backing sheet, producing a plurality of upstanding loops of
monofilament plastic. The loops are heated to set them into their
upstanding loop shape, and the hook tapes then have their loops cut
"on the bias" to form an upstanding straight portion providing no
function, and a hook-like portion.
SUMMARY OF THE INVENTION
According to the present invention, a nylon monofilament is crimped
according to a known process back on itself to provide a succession
of sawtooth hook-like portions. It s then woven or otherwise
fastened into the backing sheet to provide pluralities of aligned
loops having a plurality of hook-like portions therein. It is then
cut essentially at the top of the loop to provide two upstanding
multiple-hook-bearing portions.
It is therefore an object of the invention to improve the hook
portions of statistical area fasteners.
Another object of the invention is to provide an improved portion
of an area fastener.
Still another object of the invention is to provide a hook portion
of the above character providing multiple hook portions on each
upstanding element.
Yet another object of the invention is to provide a method of
manufacturing the hook portions of the above character.
Yet another object of the invention is to provide methods and
separable fasteners of the above character which are convenient and
economical to manufacture according to known processes.
Other objects of the invention will in part be obvious and will in
part appear hereinafter.
The invention accordingly comprises the several steps and the
relation of one or more of such steps with respect to each of the
others, the apparatus embodying features of construction,
combinations and arrangement of parts which are adapated to effect
such steps, and the article which possesses the characteristics,
properties and relation of elements, all as exemplified in the
detailed disclosure hereinafter set forth, and the scope of the
invention will be indicated in the claims.
THE DRAWINGS
For a fuller understanding of the nature and objects of the
invention, references should be had to the accompanying drawing, in
which:
FIG. 1 is a schematic side elevation view of apparatus according to
the invention for producing a crimped monofilament hook-forming
element;
FIG. 2 shows the manner in which the hook-forming element fastened
to a backing sheet is cut according to the invention.
FIG. 3 shows the resulting multiple-hook-bearing upstanding
elements;
FIGS. 4 and 5 illustrate the way a statistical hook and loop area
fastener according to the invention may be fastened together with
hooks engaging loops; and
FIG. 6 illustrates the manner in which the hook-like portion may be
woven into a fabric backing sheet in aligned rows for ease of
multiple cutting of the aligned rows of loops.
The same reference characters refer to the same elements throughout
the several views of the drawing.
SPECIFIC DESCRIPTION
Referring now to FIG. 1, a plastic monofilament 10 of nylon or the
like is extruded from an extruder head 12. While it is still in its
thermoplastic state, it passed through a pair of aligned,
oppositely sawtoothed, forming rolls 14 and 16, which form the
filament 10 into a plurality of zigzag multiple sawtooth hook-like
portions 18, facing in each direction along the filament and thus
being bidirectionally exposed.
Now referring to FIG. 2, the filament 10 is then woven or otherwise
passed through a backing sheet 20 to form a plurality of looped
portions 22, each having a plurality of, and preferably more than
four, hook-like portions 18. The loop is then cut at its apex, as
indicated at 24, by a cutting knife 26 in a manner comparable to
that in which hooks are cut on the bias according to the prior art,
except that the cutting is done, as previously mentioned, at the
apex 24 of each upstanding loop 22. Because the filament 20 is
elastic, it springs open to form upstanding hook-like portions 28
and 29 as shown in FIG. 3, each preferably bearing at least two
hook-like portions 18 exposed for egagement with the multiple loops
30 of a loop sheet formed according to the prior art.
Thus, when a loop sheet 32 according to the prior art as shown in
FIG. 4 is pressed down against a hook sheet, generally indicated at
34 and formed according to the invention, with the upstanding
multi-hook elements 28 and 29 the loops are entangled and caught on
the hook portions 18 of the hook elements 28 and 29 to form the
unitary fastener 36 illustrated in FIG. 5.
Those skilled in the art will understand that one convenient method
of manufacturing a hook tape 38 is illustrated in FIG. 6. There a
plurality of monofilaments 10 are woven into the backing cloth tape
40 such that the loops 22 formed therein are aligned into row so
that when an elongated knife 26 is inserted therein a plurality of
loops 22 may be cut to form the completed tape indicated at the
right hand portion of FIG. 6. A plurality of generally parallel
knives 26 with upwardly facing cutting edges may be employed
simultaneously if desired.
Summarizing, it will be seen that I have provided multiple
upstanding hook-like portions on a statistical hook area fastener,
by preforming the hook filaments into a plurality of hooks, weaving
or otherwise affixing the hook element into a plurality of loops on
a backing sheet, and cutting the loops to provide a plurality of
upstanding hook elements each having a plurality of hook portions
thereon.
It will thus be seen that the objects set forth above, among those
made apparent from the preceding description, are efficiently
attained, and since certain changes may be made in carrying out the
above process, in the described product, and in the constructions
set forth without departing from the scope of the invention, it is
intended that all matter contained in the above description or
shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended
to cover all of the generic and specific features of the invention
herein described, and all statements of the scope of the invention
which, as a matter of language, might be said to fall
therebetween.
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