Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to a new and improved method
of and means for making variable width zipper profile film of the
type which is especially useful in making so-called zipper bags
or other articles provided with resilient, profiled reclosablc
S flexible fasteners and wherein the fasteners are closed or opened
by elastic deformation.
For various purposes, and especially for the manu-
facture of bags, mating profiled resiliently flexible extrude(J plastic
fastener strips are joined to film web which may be extrude l
10 plastic material. The fasteners may be of the type which can be
joined to provide a closure by finger pressure or by means of a
slider. The profiles of the fasteners are elastically deformable
for this purpose. ~
Bags made from such material, which may be ~-
identified as zipper profile film web, comprise thin film web walls
joined along opposite sides to form a ~J shaped bag body wherein
either opposite end of the bag may be initially open or openable
and the remaining end closed. For example, the bottom of the
bag may remain open until the bag has been filled with a contents
such as merchandise and then sealed shut. On the other hand, the
upper or top end of the bag may remain open or be readily
openable to be filled with the contents. Separable profileclfasteners,
generally along the top of the bag, permit opening and closing of
the bag for access to the contents and for reclosing the bag as
desired. Bags oF this general type have been widely used for
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packaging, especially in the retail trades for purveying consumer
products such as food, clothing, tools, etc. Visual inspection of
the contents is facilitated by having the bag walls formed from
a transparent plastic film web material.
According to prior methods of manufactu r~, the
- plastic film web and fastener strips have been formed in a
common extrusion operation and generally from tllc same pla stic
material. This is a relatively slow process alld presents some
difficulties resulting from the great difference in mass of thc film
and the mass of the fastener strips at the location these are
coextruded. To alleviate this difficulty, it has been proposel to
prefabricate the fastener strips and the film web and then join
the same either by electronic fusion or adhesively.
However, according to prior arrangements, varia-
tions in the width of the zipper profile film web has required
shutting down the production apparatus to effect adjustments as to
width, that is, as to the positioning of the fastener strips relative
to one another on the film web, and comprising changes in
extrusion dies, changes in the mechanisms for bringing the
fastener strips and the film web together, while the apparatus
remains idle until any changes have been made . That ha s been
especially wasteful procedure where only relatively short runs
of the zipper profile film web of any particular widths have been
needed .
Therefore, it is an important object of the present
invention to overcome the disadvantages deficiencies, ineffi-
ciencies, shortcomings and problems inherent in prior methods
and apparatus and to provide a new and improved method of and
means for making variable widths of zipper profile film accord-
ing to which the width of the zipper profile film web can be
expeditiously varied without interrupting continuous production.
The present invention provides a new method of mak-
ing zipper profile film web, comprising extruding a plurality
of separate plastic fastener strips in close proximity to one
another and at the same production speed, effecting continuous
running travel of a web of substantial width at the same speed
as the extrusion production speed of said fastener strips, ad-
justing respective positions of the fastener strips transverse-
ly relative to the web and into substantially spaced relation
to one another, then guiding the fastener strips as thus
adjusted as to position, without interruption after extrusion ;~
of the strips, into longitudinal positions convergently onto
the web, and permanently securing the travelling fastener :
strips to the travelling web.
The invention also provides new apparatus for mak-
ing zipper profile film web, comprising means for extruding a
plurality of separate plastic fastener strips in close proxi-
mity to one another and at the same production speed, means
for effecting continuous running travel of a web of substant;al
width at the same speed as the extrusion production speed of
said fastener strips, means for guiding the fastener strips
from the extrusion means into longitudinal positions relative
to the web and in substantially spaced relation of the fastener strips to
one another on the web, means for selectively adjusting said guide strips
to one another on the web, means for selectively adjusting said guide
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means to effect adjustments of the respective positions of the
fastener strips transversely relative to the web, and means
for effecting convergence and for permanently securing the
travelling fastener strips to th~ travelling web.
The invention further provides a new method of mak-
ing zipper profile film web, comprising effecting continuous
running travel of a web of substantial width r extruding one
plurality of separate plastic fastener strips adjacent to one
longitudinal edge of the web and at a production speed equal
to the running travel of the web, extruding a second plurality
of separate plastic fastener strips adjacent to the opposite
longitudinal edge of the web and at a production speed equal
to the running travel of the web, guiding the extruded fasten-
er strips transversely across the web into respective longi-
tudinal positions for the fastener strips, at such longitu-
dinal positions guiding the fastener strips into parallel
longitudinal running relation with the web, adjusting the
fastener strips transversely relative to the web and to one
another, and effecting convergence and permanent securement
of the fastener strips to the travelling web.
There is also provided by the present invention a
new apparatus for making zipper profile film web, comprising
means for effecting continuous running travel of a web of
substantial width, an extruder adjacent to one longitudinal
2~ edge of the web and operating to extrude a plurality of
separate plastic fastener strips in close proximity to one
another and at a production speed equal to the running speed
of the web, a second extruder adjacent to the opposite longi- :
tudinal edge of the web and operative to extrude a plurality
.. . . .. .. .. . . . .
of separate plastic fastener strips at a production speed
equal to the running speed of the web, guiding means operat-
ing to guide the extruded fastener strips transversely across
the web into respective longitud:inal positions for the
fastener strips, said guiding means also operating at said
lonyitudinal positions to guide the fastener strips into
parallel longitudinal running relation with the web, means for
adjusting the guiding means for adjusting the respective posi-
tions of the fastener strips transversely relative to the web,
and means for effecting convergence and permanent securing of
the travelling fastener strips to the travelling web operative
after the fastener strips have been guided by said guiding
means to said parallel running relation to the web.
Other objects, features and advantages of the inven-
tion will be readily apparent from the following description
of a representative embodiment thereof, taken in conjunction
with the accompanying drawings although variations and modifi- ;
cation may be effected without departing from the spirit and
scope of the novel concepts embodied in the disclosure and in
which:
Fig. 1 is a schematic elevational view of means for
practicing the invention.
Fig. 2 is an enlarged fragmentary side elevational -~
view taken substantially in the plane of line II-II of Fig. 1.
Fig. 3 is a schematic edge view of a film web equip- ~`
ped with fastener strips according to the present invention
and adapted for making open top bags. -~
Fig. 4 is a schematic edge view of a film web
equipped with fastener strips according to the present invention
adapted for making bottom open bags.
Fig. 5 is a fragmentary sectional elevational view
- taken substantially along the line V-V of Fi~. 2; and
Fig. 6 is a fragmentary side elevational view
similar to Fig, 2 but showing a mcdification.
On reference to Fig. 1, at least one, and in this
instance a plurality such as four continuous profiled resiliently
flexible extruded plastic fastener strips 10 and a continuous -film
web 11 which may also be formed from extruded plastic material
are caused to travel in the same lon~itudinal direction and at the
same speed. The fastener strips 10 are adjusted as to position
relative to the width of the web and to each other and guided
into convergence with the web 11, and then permanentlv secu red
to the web. For bag making, plastic material most appropriate
for the mechanical and optical qualities desired, in either or
both of the fastener strips and the film, should be chosen. For
example, the web 11 may be formed from polypropylene and the
fastener strips may be made from polyethylene where the
fastener strips and the web are to be adhesively attached to one
another. On the other hand, where the fastener strips are to be
fused to the web they may both be made from the same material,
or at least from rnaterials which are 3~usibly compatible.
An extrusion of the fastener strips 10 may be by
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means of one or more, in this instance two, extruders 12 which
extrude the fastener strips through suitab]e die orifices to
produce the desired profiled strip section. For convenience ancl
compactness of apparatus, the fastener strips produced by each
of the extruders 12 are projected from the extruder in close
proximity into and through a chilling device 13 in which thc hot
plastic extruded fastener strips are subjected to a cooling medium
such as water and from which the fastener strips travel
continuously toward union with the web 11. In the illustrated
example, two of the fastener strips 10 are produced at one side
of the web 11 and two of the fastener strips 10 are produced at
the opposite side of the web.
Although the web 11 may be supplied from a roll
where it may comprise a non-plastic material, or where it ma~
be a composite plastic and non-plastic material and thus desirably
prefabricated at a different place and at a different speed than
that of the assembl~ and joining speed of the fastener strips to
the web, in a more usual arrangement for producing bag making
zipper profile film web, the web 11 is extruded through a
suitable elongated orifice from a T-die 14 of an extruder 15
For example, the plastic film web 11 may be a flat sheet of
about 60 inches (150 cm). Since both the fastener strips 10 and
the web 11 are prefabricated before joining them and since the
fastener strips are extruded and chilled separately from the web
11, production of the fastener strips and the web and joining
them can be effected at high speed such as about 650 to lO00
feet per minute (200-300 m/mn), especially where attachment of
the fastener strips to the web is effected adhesively.
Means for guiding and applying the fastener strips
lO to the web l1 comprise, for each of the fastener strips 10,
an ang1ing guide roller 17 over which the strips are guided from
a path which generally parallels the adjacent ec3ge of the weh ll
to a direction transversely inwardly relative to said web and to
an angling roller l 8, over and from which the fastener stril-
trave1s onward again longitudinally with the web ll in the desired
orientation for assuming its attached position on the web. The
rollers 17 may be rotatably mounted in fixed position by mealls
of brackets 19 (Fig. 2) carried on a machine frame 20.
Mounting of the ang1ing rollers 18 is effected by
1~ means permitting adjusting of the fastener strips 10 transverselv
relative to the web 11 without interrupting the continuous travel
of the fastener strips and web. For this purpose, the rollers l 8 ;
are mounted on respective adjustment arms 21 extending
longitudinally relative to the travel of the web ll, with said arms
mounted adjustably on a bar or beam 22 which extends
transverse1y in a suitab1y spaced re1ation to the path of travel
of the web ll, and is fixedly mounted at its opposite ends such
as by means of rigid arms 23 to the frame 20. In one
con~enient manner of mounting the arms 21, each of them has
a rigid slide block 24 on its end opposite the supported roller
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18, with the slide block being slidably engaged on the beam 22
so as to permit incremental transverse adjustment with respect
to the web 11, To fix the block 24 in each instance releasably
in adjusted position along the beam 22, releasable retaining
means such as a set screw 25 may be carried by each of the
block s .
The length of each of the arms 21, and its spaced
relation to the path of travel of the web 11 is such that an
additional mechanism can be carried by the arm and the associa-
ted mounting block 24 for handling and attaching the associated
fastener strip 10. Desirably a fastener strip guide 27 is carriecl
by the arm 21 for accurately directing the fastener strip
convergently toward the web ll. Downstream from the guide 27,
means are provided for attaching the fastener strip 10 to the web
11, and in one desirable form comprising an adhesive applicator
28 having a nozzle 29 from which suitable adhesive 30 is
deposited between the interface area of the web 11 and the
fastener strip 10 adjacently upstream from where the web and
strip converge. Liquid adhesive is supplied to the applicator
28 from any suitable source as by means of a conduit 31.
Mounting of the applicator 28 is desirably by means of an
auxiliary arm 32 fixed to the block 2~ of the associated supporting
arm 21. After application of the adhesive 30, a presser roll 33
presses the web sections of the fastener strip 10 firmly against !;
the web 11 which at this point is supported by a backing roll 34
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mounted rotatably on the frame 20. Conveniently, the presser
roll 33 may be journaled on bearing bracket means 35 also
carried by the auxiliary arm 32, with resilient spring biasing
means 37 acting on an axle 38 of the roller 33 to thrust the
roller yieldably toward the webs of the fastener strip 10.
Although each of the arms 21 has a separate presser roll 3
associated therewith, the backing roll 34 is common to the
entire array of presser rolls, and desirablv extends entirel~
across the web 11. Through this arrangement, each of the arms
21 and the associated fastener strip guiding and attaching
mechanisms are adapted to be incrementally adjusted transversel~
relative to the web 11, for adjusting the position of the associated
fastener strip in longitudinal orientation with the web 11, fo~
any variable bag size desired to be made therefrom while the
fastener strips and the web continue travelling uninterruptedly at
high speed. It will be understood that any suitable means may
be provided downstream from the point of attachment of the
fastener strips to the web 11 for maintaining the web and
fastener strips in continuous onward travelling motion coordinated
with the speed of extrusion of the fastener strips and thc web.
For some purposes, it may be desirable to wind the fastener
carrying web on a roll. On the other hand, the fastener carrying
web may go directly to processing apparatus such as bag making
apparatus where the web may be slit into a plurality of suitable
widths zipper profile film strip sections which are suitabl~ folded
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into U shapes for forming into bag units. Any such means are
represented schematically at 20a (Fig. 2),
As best seen in Fig. 5, each of the fastener strips
10 may be of a width to carry integrally thereon a barbed male
fastener profile 39 in spaced parallel relation to a groovecl
complementary female profile 40. To accommodate the profiles
39 and 40, the presser roll 33 is provided with respective
clearance grooves 41 and 42 which also assist in guiding thc
fastener strips accurately into position on the web 11, utilizing
the profiles 39 and 40 as guide means for the strip.
For high speed operation, the adhesive 30 is
desirably a hot thermofusible synthetic resin adapted to bc
applied at a temperature of about 390 to 460"F. (150G - 190 c)
in a layer of about . 00~ inch (.10 mm) at a speed up to 1000 f~
per minute (300 m!mn), sufficiently tacky to retain the attache:3
fastener strip on the web and to set in about 3 to 5 seconds
after being applied.
Where it is preferred to attach the fastener strip ~ -
to the web by electronic or heat fusion, the arrangement of
Fig. 6 may be employed. For this purpose, the guiding and
supporting arm 21' may be of substantially the same construction
and function similarly as the arm 21 already described, supported
on a slide block 24' slidably mounted on the beam 22' to which
it is adapted to be locked in adjusted position by means of a
set screw 25'. In addition the arm 21' carries the guide 27'.
However in this instance, there is mounted on thc: block 24' in
association with the arm 21' an electronic welding roll 43
rotatably carried by a bracket 44 Oll an auxilliary arm 45 suppor-
ted by the block 24'. To accommoclate the fastener strip profiles,
5 the welding roll 43 is grooved similarly as the roll 33. The
roll 43 is suitably electronically or heat powered and presses the
webs of thc fastener strip 10 against the web 11 towarcl a
cooperating backing roll 47 which may be supported by bracket
means 48 carried by the machine frame and biased toward thc
10 back of the web 11 by means of biasing springs 49 acting against
an axle 50 of the roll 47. Through this arrangement, as the
fastener strip 10 converges with the web 11 at high speed, the
roll 43 permanently e1ectronically or heat welds the strip to the
web .
Whether the fastener strips are adhesively, electroni-
cally or heat attached permanently to the film web, the reclosable
plastic fastener strips may carry fastener profiles arranged for
either top opening or bottom opening bags. For top opening bag
purposes, the arrangement of fastener strips on the web may bc
20 substantially as exemplified in Fig. 3 wherein the web 11' has
attached thereto at suitably spaced intervals fastener strips 1()'
carrying a pair of integral laterally spaced male profiles 39'
with such strips 10' alternating with fastener strips 10" having
a pair of integral laterally spaced female profiles 40'. ln
25 suitably spaced adjacency to the respective opposite longi tudinal
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edges of the sheet web 11' are attached a fastener strip 10a
having thereon a female profile 40" and a fastener strip lOb
having thereon a single male profile 39". The fastener strips
10', 10", 10a and 10b are so disposed relative to one another
that when the web 11' is severed along lines 51 medially between
the male and femal profile pairs 39' and 40', respectively thc
resulting zipper profile film sections are adapted to be folàed
along lines 52 midway between adjacent male and female profi]es
to bring said male and female profiles into fastened relationship,
thereby providing open top bags wherein the portion of the film
between the fastener strips is foldecl to provide the walls of the
bag with said bag having a closed bottom and being openable at
the top by separating the resiliently flexible zipper fastener. It
will be understood, of course, that as is usual practice, the
folded film section will be transversely sealed at suitable
intervals to provide bag units. It will be observed, of course,
that for ma~imum yield, the web 11' in the illustrated example
has been provided with six fastener strips. This shows that there
is no necessar~ limit on the number of fastener strips that may
be applied to a travelling film web, within the parameters of
practicability and apparatus capacity.
For producing bottom open bags, having reference
to Fig. 4, the web 11 having attached thereon the fastener strips
10 each provided with an integra] male profile 39 and an integral
female profile 40, is adapted to be severed along longitudinal
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lines 53 midway between the fastener strips 10 and folded along
longitudinal lines 54 midway between the profiles 39 and 40 of
each of the strips to bring the profiles into mating fastener
c]osed relation. Thereby the portions of the zipper profile film
sections at each side of the fastener strip 10 in each instance
provide wall panels for open bottom bags. It will be understood
that after folding of the web film sections, the sections are
transversely sealed at suitable intervals and separate~ into hag
units. Such open bottom bag units can then be filled thro~lgll
their open bottoms and the openings sealed to provide bags which
are completely hermeticallv sealed until they are opened for access
to the contents by severance, as by snipping the bags open a~ong
substantially the fold lines 5~, whereby the fasteners of thc bag
can then be opened by manually separating the fastener profiles
39 and 40. After thus opening the bags, they can be readily
reclosed by again joining the fastener profiles 39 and 40.
Although two examples of fastener and film web ori-
entation and bag making potential have been described, it will be
apparent that numerous and varied other fastener orientations and
arrangements may be attained according to the principles of the
present invention. A salient new and improved result attained by
the present invention is the capability of varying the width of the
zipper profile filrn, that is the strip sections into which the
sheet web is severed, in any desired combination without ever
having to stop the continuous running travel of the fastener strips
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and web. This result is achieved by the facility of incremental
transverse adjustment of the positions of the fastener strips on
the travelling web as desired without interrupting continuous high
speed travelling flow of the fastener strips and the web. Such
freedom from interruption in the continuous travelling flow includes
the extrusion process.
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