U.S. patent number 3,790,992 [Application Number 05/263,792] was granted by the patent office on 1974-02-12 for profiled closing members with slide.
This patent grant is currently assigned to Minigrip, Inc.. Invention is credited to Andre Herz.
United States Patent |
3,790,992 |
Herz |
February 12, 1974 |
PROFILED CLOSING MEMBERS WITH SLIDE
Abstract
A method of making bags and the bags resulting therefrom wherein
the bags have a top edge and first and second side edges and
interlocking rib and groove element at the top edge with a slider
straddling the top edge and the slider having a back and downwardly
projecting sides with the sides being closer together at a closing
end of the slider which extends toward the first edge of the bag
and being wider apart at the opening end of the slider which
extends toward the second edge of the bag and with a finger between
the sides at the opening end and the bag having heat seals joining
the rib and groove elements and the heat seal being wider at the
first edge than the second edge and being of a width at least equal
to the length of the slider from its closing end to the finger so
that the slider will remain fully on the bag at the end of its
travel when opening the bag.
Inventors: |
Herz; Andre (Nesles la Vallee,
FR) |
Assignee: |
Minigrip, Inc. (Orangeburg,
NY)
|
Family
ID: |
9079616 |
Appl.
No.: |
05/263,792 |
Filed: |
June 19, 1972 |
Foreign Application Priority Data
|
|
|
|
|
Jun 30, 1971 [FR] |
|
|
7123942 |
|
Current U.S.
Class: |
24/400; 24/427;
383/64; 156/251 |
Current CPC
Class: |
B65D
33/2591 (20130101); Y10T 156/1054 (20150115); A44B
19/16 (20130101); A44B 19/267 (20130101); Y10T
24/2534 (20150115); Y10T 24/2582 (20150115) |
Current International
Class: |
A44B
19/10 (20060101); A44B 19/26 (20060101); A44B
19/16 (20060101); A44B 19/24 (20060101); B65D
33/25 (20060101); A44b 019/24 (); B65d
033/24 () |
Field of
Search: |
;150/3 ;24/21C ;229/69
;156/251 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
270,934 |
|
Nov 1966 |
|
AU |
|
1,551,228 |
|
Nov 1968 |
|
FR |
|
Primary Examiner: Griffin; Donald A.
Attorney, Agent or Firm: Hill, Sherman, Meroni, Gross &
Simpson
Claims
I claim as my invention:
1. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like comprising in
combination,
a pair of flexible plastic sheets having a top edge and first and
second side edges with separable fastener means at the top edge
having releasably interlocking rib and groove elements on the
facing surfaces thereof,
a straddling slider for joining or releasing the separable
fasteners having a back for moving along the top edges of the
fasteners with sides projecting from the back and extending from an
opening end of the slider to a closing end,
said sides being spaced wider apart at the opening to permit
separation of the rib and groove elements and being spaced
sufficiently close together at the closing end to press the rib and
groove elements into interlocking relationship as the slider is
moved in a fastener closing direction toward the second edge of the
sheets,
a separating finger on the slider extending between the sides at
said opening end for separating the rib and groove element as the
slider is moved in a fastener opening direction toward the first
edge of the sheets,
and means permanently joining said rib and groove elements at the
first edge a distance in from the edge at least equal to the length
of the slider from the closing end to said finger so that the
finger engages said joining means when the slider is moved to the
first edge and complete slider remains on the fastener means,
and means on the slider interengaging the fastener preventing the
slider from being lifted off of the top edge of the fastner while
the slider straddles the fastener.
2. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like constructed in accordance
with claim 1 wherein said joining means is a heat seal connecting
the rib and groove elements.
3. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like constructed in accordance
with claim 2 wherein the heat seal extends in from the first edge
equal to the length of the slider from the closing end to said
finger.
4. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like constructed in accordance
with claim 1 and including means at the lower edges of said slides
interengaging with the sheets for holding the slider onto the top
edges of the sheets.
5. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like constructed in accordance
with claim 1 wherein said finger includes means interengaging with
the fastener means for preventing the slider from being lifted off
of the edge of the sheets.
6. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like constructed in accordance
with claim 1 and including means permanently joining the rib and
groove elements at said first and second edges with the means at
said second edge being narrower than the means at said first
edge.
7. A reclosable fastener structure for releasably joining the top
edges at the opening of a bag or the like constructed in accordance
with claim 1 wherein said top sheet edges continue to form the
sides of a bag.
8. A reclosable fastener structure for releasably joining the top
edges at the opening of the top of a bag or the like
comprising,
first and second pairs of flexible plastic sheets each pair having
a top edge and first and second side edges with the second edge of
the first pair being adjacent the first edge of the second pair of
sheets and the sheets having separable fastener means at the top
edge with releasably interlocking rib and groove elements on the
facing surfaces thereof,
a straddling slider for each pair of sheets for joining and
releasing the top edges with the slider having a back for sliding
along the top edges and sides projecting therefrom and extending
from an opening end of the slider to a closing end,
the sides of said slider being spaced wider apart at the opening
end to permit separation of the rib and groove elements and being
spaced sufficiently close together at the closing end to press the
rib and groove elements into interlocking relationship as the
slider is moved from the first to the second edge of the
sheets,
a separating finger on the slider extending between the sides at
said opening end for separating the rib and groove elements as the
slider is moved toward the first edge of the sheets, heat seal
means joining two sheets of each pair to each other at the second
top edge of the first pair and the first top edge of the second
pair with said seal extending further into said second pair of
sheets than into said first pair of sheets and extending into said
second pair of sheets a sufficient distance to stop the slider so
that its closing end remains on the sheets,
and the first pair of sheets being joined to each other by a
cross-seam along their second edge and the second pair of sheets
being joined to each other by a cross-seam along their first edge
with said cross seams being adjacent each other and the pairs of
sheets being separated by being severed from each other.
9. A reclosable fastener structure for releasably joining the top
edges at the opening of the top of a bag or the like constructed in
accordance with claim 8 wherein said first pair of sheets are
joined to each other by a cross-seam which comprises a wire seal
along their second edge with said wire seal simultaneously also
forming the seal along the first edge of the second pair of sheets
with the pairs of sheets being separable by severing the first pair
of sheets from the second pair of sheets.
10. The method of forming a plurality of bags from pairs of
superimposed sheets having a top edge with fastener means extending
therealong including releasably interlocking rib and groove
elements on the facing surfaces thereof and including straddling
sliders for each bag formed from said sheets with the sliders
having a back for sliding along the top edges with sides projecting
therefrom and extending from an opening end of the slider to a
closing end with the sides being spaced wider apart at the opening
end to permit separation of the rib and groove elements and being
sufficiently close together at the closing end to press the rib and
groove elements into interlocking relationship, and the slider
including a separating finger between the sides at the opening end
for separating the rib and groove elements as the slider is moved
in a fastener opening direction, the method comprising,
forming a top end seal between the rib and groove elements with the
seal extending into one bag a less distance than into an adjacent
bag with the sliders positioned on the bags so that the closing end
of the sliders face the wider seals so that the fingers of the
slider engage the front of said seals and the sliders are held onto
the bag as they move to the far end of their travel in separating
the rib and groove elements,
and thereafter forming a seal across the sheets between bags and
severing the bags from each other.
Description
BACKGROUND OF THE INVENTION
The invention relates to improvements in fasteners for plastic bags
or the like wherein the fasteners include releasably interlocking
rib and groove elements with a slider for opening or closing the
rib and groove elements. More particularly, the invention relates
to an improved structure which limits the travel of the slider in
its movement in an opening direction so that it does not wedge or
stick and does not come off the end of the fastener strips.
In plastic fasteners for bags such as the type with which the
present invention is concerned, releasably interlocking rib and
groove elements extend along the top of the bag from a first edge
to a second edge. The rib and groove elements are on the inside
facing surfaces of the sheets of the bag and a straddling slider
moves along the top of the bag. The straddling slider has a back
and sides which extend along the outside of the rib and groove
elements, and the sides are closer together at a closing end of the
slider so that the rib and groove elements are pressed into
interlocking relationship as the slider moves from the first to the
second edge of the bag. At the opening end of the slider, the sides
are further apart and a finger extends down between the slides for
separating the interlocking rib and groove elements as the slider
is moved from the second to the first edge of the bag.
When the bag is opened, the only thing to stop the slider in
structures heretofore available is the seam at the edge of the bag,
and when the slider finger comes into contact with it, most of the
slider body is already off of the bag and, therefore, can easily be
twisted off. If not twisted off, it may wedge or jam or become
cocked or twisted so that it is not easy to start it and move it
back in the direction to close the bag.
It is accordingly an object of the present invention to provide an
improved structure wherein the slider is stopped in a position so
that it remains fully on the bag at one edge and cannot be twisted
off and does not wedge or jam, but can easily be again pushed in
its closing direction.
Another object of the invention is to provide an improved method
for manufacturing a series of bags providing bag structures of the
type above described wherein structures are made by a minimum of
steps for rapid and efficient manufacture resulting in a reduction
of cost.
Other objects and advantages will become apparent from the teaching
of the principles of the invention from which equivalent structures
and methods will be become apparent to those versed in the art, as
disclosed in the specification, claims and drawings, in which:
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of bags constructed and manufactured
in accordance with the principles of the present invention;
FIG. 2 is a vertical sectional view taken substantially along line
II--II of FIG. 1;
FIG. 3 is a vertical sectional view taken substantially along line
III--III of FIG. 1;
FIG. 4 is a fragmentary end elevational view taken substantially
along line IV--IV of FIG. 1; and
FIG. 5 is an elevational view illustrating steps in the method of
making bags in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As illustrated in FIGS. 1 through 3, the structure includes
flexible plastic bags formed of plastic sheets 1 and 2. These
sheets form a bag 3 which has a top edge 27, and a first side edge
28 and a second side edge 29.
Along the top edge of the bag are fastener means which include
flexible rib and groove elements with the rib 6 being sized and
shaped to be releasably interlockable in the groove 5 of a groove
element 4.
The rib and groove elements are formed of plastic as are the sheets
1 and 2 which form the walls of the bag, and in one form these
elements may all be formed in a single extrusion method by being
extruded from a plastic die. While the rib and groove elements are
shown as being integral with the sheets, it will be understood that
the features of the invention will also apply to separate closure
strips which have rib and groove elements and which are attached to
sheets.
When the rib and groove elements are pressed together by the
application of a lateral pressure, they interlock as shown in their
relative positions of FIG. 3. When they are forcibly pulled apart
as by applying a separating pressure between them, they separate as
illustrated in FIG. 2.
For joining or separating the rib and groove elements which closes
or opens the top of the bag 3, a straddling slider 7 is positioned
at the top edge of the bag. The slider has a back 8 which slides
along the top edge and sides 9 and 10 mounted on the back that
extend downwardly along the outer surfaces of the rib and groove
elements.
The slider has a closing end 11 and an opening end 12 with the
closing end extending toward the first edge 28 and the opening end
extending toward the second edge 29.
At the closing end 11 of the slider, the sides 9 and 10, as shown
in FIG. 3, are sufficiently close together so that they press the
rib and groove elements into interlocking position. This will occur
as the slider is moved in a closing direction from the first edge
28 to the second edge 29.
At the opening end 12 of the slider, a separating finger 13 is
mounted on the back 8 and extends down between the sides 9 and 10.
The finger forces the rib and groove elements apart to open the top
of the bag, and the sides 9 and 10 are wider spaced at the opening
end to permit this separation of the rib and groove elements.
Means are provided for holding the slider 7 in its straddling
position at the top edge of the bag. One of these means are shown
by the upwardly facing shoulders 14 and 15 at the lower edges of
the side walls. These shoulders are locked beneath the bulges
formed on the outer surfaces of the sheets 1 and 2 by the rib and
groove elements 4 and 5. The slider is also held onto the top of
the bag by shoulders formed by an enlarged head 16 at the lower end
of the separating finger 13. These shoulders lock beneath the rib
and groove element and also thus lock the slider in its straddling
position onto the top edge of the bag.
As will be observed from the drawings and the foregoing
description, the slider will be held onto the top edge of the bag
in all positions. However, if the slider could be pulled off of the
end of the bag, such as moving too far to the right toward the
first edge 28 in FIG. 1, it could twist upwardly and wedge or jam
or be lifted fully off of the top edge of the sheets. To prevent
this, a stop 18 is provided which is engaged by the separating
finger 13 as the slider is moved to the edge of the bag to limit
the travel of the slider to traveling no further than the position
shown in FIG. 1. The stop 18 is preferably in the form of a
cross-seal joining the rib and groove elements which prevents them
from separating. The stop may be provided by a seal created by
ultrasonic welding or by the application of a heated instrument to
join the rib and groove elements, but an important feature of its
construction is its location. That is, it extends inwardly from the
first edge 28 a distance shown at X which is at least the length of
the slider from its closing end 11 to the inner surface 21 of the
separating finger 13.
In the manufacture of the bags as shown in FIG. 2, the bags are
formed from a front sheet which becomes the front wall 1 of the bag
and a continuation of said front sheet that is folded under itself
to become the rear wall 2 of the bag 32 of FIG. 1. These sheets are
continuous and have at their top edge the fastener means comprised
of the rib and groove elements 5 and 6. To form bags cross-seals
are made which form the side edges of the bags. As shown in FIG. 5,
the bags have their cross-seals made so as to form a first side
edge 28 of the bag 32 and a second side edge 25 of the bag 31.
Individual bags are severed from each other along line 23. The
cross-sealing and severing is accomplished either in a single
operation by using a hot wire that seals and cuts or in two
operations by the application of a broader heated sealing bar which
is then cut through its center by a knife. At the top of the bag,
prior to the cross-seal, the stop 18 is formed such as by
ultrasonic sealing. The provision of a stop is provided for
successive bags as shown by the sealed areas 26 and 36. Stop 26
extends a greater distance into the second bag 32 than into the
first bag 31. That is, the portion 26b of the seal 26 is narrower
than the portion 26a. Portion 26b provides the stop for the slider
35 at the end of its travel when it closes the bag 31. Portion 26a
provides the stop for the slider 7 at the end of its travel when it
opens the bag 32. Thus, in a single manufacturing operation
correctly sized stops are made for both the first and second bags
31 and 32 by virtue of the selective positioning of the overall
area 26.
The slide 7 is formed of suitable material such as being molded
from relatively hard plastic. The slide may be positioned by
various methods such as by having its walls forcibly separated and
pushed into its straddling position over the top of the bag. While
the method of FIG. 5 shows the simultaneous manufacturing of a
number of bags, the end seals at the first and second edges of the
bag can be placed on the bags at a separate time. The bonding or
welding of the edges of the bags and the formation of the stop can
be formed by various types of equipment and can utilize the method
of ultrasonic welding with the aid of electrodes or heads, one type
of which is known to the art as "sonotrode."
* * * * *