U.S. patent number RE34,263 [Application Number 07/809,271] was granted by the patent office on 1993-05-25 for end closure having a push open lid portion.
This patent grant is currently assigned to The Specialty Packaging Group, Inc.. Invention is credited to James Kick, John vanKerkhoven, deceased.
United States Patent |
RE34,263 |
vanKerkhoven, deceased , et
al. |
May 25, 1993 |
End closure having a push open lid portion
Abstract
An end closure for a container for grated or powered products
having a push open lid portion for providing access to material
within the container and a rotatable closure portion for
selectively closing off the opening defined by the push open lid
portion. The push open lid portion includes elements on the
openable lid portion which cooperate with corresponding gripping
elements defined on the undersurface of the end closure so the
latter will engage the former to retain the lid portion in its open
disposition.
Inventors: |
vanKerkhoven, deceased; John
(late of Wausau, WI), Kick; James (Ellisville, MO) |
Assignee: |
The Specialty Packaging Group,
Inc. (Wausau, WI)
|
Family
ID: |
27012759 |
Appl.
No.: |
07/809,271 |
Filed: |
December 16, 1991 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
389581 |
Aug 4, 1989 |
04969572 |
Nov 13, 1990 |
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Current U.S.
Class: |
220/253; 220/268;
220/379; 222/153.06; 222/541.6; 222/548; 222/555 |
Current CPC
Class: |
B65D
47/265 (20130101); B65D 47/36 (20130101); B65D
51/20 (20130101); B65D 51/222 (20130101); B65D
2251/0025 (20130101); B65D 2251/0071 (20130101); B65D
2251/0087 (20130101); B65D 2251/0093 (20130101) |
Current International
Class: |
B65D
47/04 (20060101); B65D 47/00 (20060101); B65D
51/18 (20060101); B65D 51/22 (20060101); B65D
47/36 (20060101); B65D 47/26 (20060101); B65D
51/20 (20060101); B65D 051/18 () |
Field of
Search: |
;220/253,254,258,259,268,335,336,379,744 ;222/153,541,548 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Shoap; Allan N.
Assistant Examiner: Stucker; Nova
Attorney, Agent or Firm: Cushman, Darby & Cushman
Claims
What is claimed is:
1. An end closure for a container comprising:
a substantially planar first lid portion including means for
engaging an upper rim of a container to be closed;
a second substantially planar lid portion rotatably mounted to an
upper surface of said first lid portion, said second lid portion
having an opening defined therethrough, sealing means for sealing
about the periphery of the opening between the first and second lid
portions; and
an openable lid portion defined in said first lid portion, said
openable lid portion including a flexible hinge extending along a
first edge thereof and a frangible coupling extending along the
remaining edges thereof whereby when a force is applied to the
upper surface of said openable lid portion, the frangible seal is
broken and the openable lid is pivoted about the hinge, a bottom
surface of said first lid portion including at least one gripping
element, a bottom surface of said openable lid portion including at
least one tab element positioned thereon so that when pressure is
applied to said openable lid portion and said openable lid portion
pivots about said hinge, said gripping element engages said tab so
as to retain said openable lid portion in an open disposition.
2. An end closure as in claim 1, wherein said opening defined
through said second lid portion is substantially semicircular in
shape.
3. An end closure as in claim 1, wherein said openable lid portion
is substantially semicircular in shape, said frangible seal being
defined along an arc of said semicircular openable lid portion and
said hinge portion being defined along the straight edge of said
semicircular openable lid portion.
4. An end closure as in claim 1, wherein there are two tab elements
defined on said bottom surface of said openable lid portion,
adjacent each longitudinal end of said hinge portion.
5. An end closure as in claim 4, wherein there are two gripping
elements defined on the bottom surface of said first lid portion,
each said gripping element including a substantially vertical
portion and an overhanging portion, each said gripping element
being defined adjacent a longitudinal end of said hinge element so
that when said openable lid portion is pivoted about said hinge,
said tab elements are deflected by and snap past said overhanging
portion so that said gripping elements engage and lock said tab
elements to retain said openable lid portion in an open
disposition.
6. An end closure as in claim 1 wherein said at least one tab
element is comprised of a depending wall member and wherein said
gripping element is comprised of a depending member having an end
wall and at least one sidewall, at least one flange extending
outwardly from said end wall so as to overhang said at least one
side wall a distance sufficient to intercept said tab element.
7. An end closure as in claim 6 wherein said at least one side wall
has a first width and said at least one flange has a second width
less than said first width.
8. An end closure as in claim 6 wherein said tab element further
includes reinforcing means extending between said lid portion and a
portion of said wall member for reinforcing said wall member so
that the wall member can bend relative to the reinforcing
means.
9. An end closure as in claim 6 wherein said wall member includes a
side that engages said at least one flange, wherein at least a
portion of said side directed toward said at least one flange is
beveled.
10. An end closure for a container comprising:
a substantially planar first lid portion including means for
engaging .[.an upper rim of.]. a container to be closed;
a second substantially planar lid portion rotatably mounted to
.[.an upper surface of.]. said first lid portion, said second lid
portion having an opening defined therethrough.[., sealing means
for sealing about the periphery of the opening between the first
and second lid portions.].; and
an openable lid portion defined in said first lid portion.[., said
openable lid portion including.]. .Iadd.by.Iaddend. a flexible
hinge extending along a first edge thereof and a frangible coupling
extending along the remaining edges thereof whereby when a force is
applied to the upper surface of said openable lid portion, the
frangible seal is broken and the openable lid is pivoted about the
hinge, a bottom surface of said first lid portion including at
least one gripping element, a bottom surface of said openable lid
portion including at least .[.one tab.]. .Iadd.a first.Iaddend.
element positioned thereon so that when pressure is applied to said
openable lid portion and said openable lid portion pivots about
said hinge, said gripping element engages said .[.tab.]. .Iadd.at
least first element.Iaddend. so as to retain said openable lid
portion in an open disposition.
11. An end closure as in claim 10 wherein said at least first
element comprises a flexible tab member and said gripping element
comprises a member extending downwardly from said bottom surface
terminating at an end having a flange extending radially outwardly
therefrom positioned to intercept said tab member.
12. An end closure as in claim 10 wherein said at least first
element comprises a pair of spaced apart downwardly extending wall
members and said gripping element comprises a member extending
downwardly from said bottom surface and having a predetermined
width, said pair of members being spaced apart and distance less
than said predetermined width so that said gripping element will be
frictionally engaged between said pair of members when said lid
portion pivots into its open disposition. .Iadd.
13. An end closure as in claim 1, wherein said sealing means
comprises a rib depending downwardly from a bottom surface of said
second lid portion..Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to end closures for containers having
a push open lid portion for providing access to material within the
container. The end closure includes a base portion fixed to the
container having an initially closed lid or flap portion and a flat
bottomed rotatable closure portion for selectively closing off the
opening defined by the push open lid portion. The rotating portion
is retained on the base by its marginal edges so that the base
remains intact until opened. More particularly, the present
invention relates to an end closure having a push open lid portion
and which includes one or more elements for cooperating with
corresponding gripping elements to hold the lid portion in its open
position.
2. Description of the Related Art
Many food and drink products such as grated cheese, herbs and
seasonings, and powdered drinks are provided in containers with
plastic closures having a rotatable portion with a permanent
opening through a portion thereof which selectively provides access
to an opening through a lower portion of the container closure. The
opening through the lower portion is typically defined by an
openable lid portion which is pushed towards the container interior
so as to break a seal defined between the openable lid portion and
the remainder the closure. After the frangible seal is broken, the
openable lid portion flexes or bends about a "living hinge" which
permanently connects the lid portion to the remainder of the
closure. In this manner, the end closure can be used to seal the
contents of the container prior to use and, when it is desired to
access the container contents, the rotatable portion of the lid can
be rotated so that the opening therethrough is aligned with the
openable lid portion. Pressure is then applied to the openable lid
portion to punch open the same and cause the openable portion to
bend about the living hinge. When it is desired to temporarily
close off the thus opened lid, the rotatable portion of the lid is
rotated to cover the opening defined by the openable lid
portion.
Such containers are advantageous as they allow selective access to
the container contents while providing a closure for the contents
between uses. However, a disadvantage with such end closures is
that the lid portion which has been pushed open, due to the
resilience of the living hinge, tends to flex back towards its
closed portion thereby restricting the size of the pour opening.
This particularly occurs when the container is inverted to pour
powdered material or the like from therewithin. Occasionally, the
lid portion can almost completely block the opening in the closure.
It would therefore be desirable to provide a structure which
retains the openable lid portion in its open position so that it
will not interfere with access to the container contents.
FIGS. 1-7 show various prior attempts to develop end closures that
exhibit a type of flat rotor that was rotatably retained on a base
without use of a rivet type connector or a mechanism to hold a
press-open lid in an open position.
FIGS. 1 and 2 correspond to a type of end closure suitable for
placement at the end of a container to close the interior. The end
closure is comprised of a base and a rotor retained on the base and
in a central portion of the base which extends radially outwardly
from the rotor. The periphery of the rotor is provided with a
raised or upwardly extending edge that includes a substantially
C-shaped cross-section annular ring that corresponds to a reverse
C-shaped cross-sectional retaining groove formed within the base.
The bottom surface of the rotor was essentially a flat planar
surface and included a cut-out opening and shaker openings. The
base include a smile-shaped knockout panel which would be opened by
removing the entire piece of plastic. The base was also
characterized by two levels, one corresponding to the surface, that
extended radially outwardly from the rotor, the other located
beneath the rotor.
The end closure shown in FIGS. 3-5 is another version where the
rotor, so marked, also had a flat planar bottom surface. The rotor
was held in the base, as marked, by means of an annular extension
projecting slightly beyond the peripheral edge of the rotor and a
mating groove formed in the base. Both the annular extension and
groove were radiused. The bottom surface of the rotor was spaced
above the upper surface of the base against which it was positioned
forming an open space therebetween in which debris or material from
the container could collect. Also, the radiused extension/groove
approach for retaining the rotor on the base was not sufficiently
positive to hold the rotor in place and provide a suitable seal for
the contents inside the container.
The end closure shown in FIGS. 6-7 shows a closure that holds the
openable lid open. The bottom plan view of the base in FIG. 6 and
the cross-sectional view in FIG. 7 shows the use of two tapered
conical projections that extended downwardly from the bottom
surface of the base toward the interior of the container on which
the end closure would be used. The push open lid or flap is
characterized by a straight hinge along its rear edge. Two straight
sides diverge at oblique angles away from opposing ends of the
hinge toward the front of the lid terminating at an arched front
edge which joins the outer ends of those straight sides. The
straight sides provide a special shape that will pass beyond the
tapered projections to the position shown in FIG. 7 with minimum
interference yet provide sufficient contact so that the projections
hold the flap open. Depending upon the stiffness of the plastic of
the hinge and the lid, the lid would need to be bent beyond
90.degree. to move the lid beyond the projections in order to
arrive at the position shown for the flap in FIG. 7. FIGS. 6a and
6b show top and bottom plan views of the rotor used on this end
closure. The rotor was characterized by planar top and bottom
surfaces, by a square cornered peripheral edge that mated with a
radiused groove, as shown in FIG. 7, which was similar to the
groove shown in FIG. 5 for retaining the rotor.
SUMMARY OF THE INVENTION
It is a object of the present invention to provide a container
closure as described above which includes a means for maintaining
the pushed open lid portion in its open disposition. These and
other objects are realized in accordance with the present invention
by providing an end closure for a container having a substantially
planar first lid portion including means for engaging an upper rim
of a container to be closed and a second lid portion rotatable
mounted to the upper surface of the first lid portion, the second
lid portion having an opening defined therethrough. An openable lid
portion is defined in the first lid portion and includes a flexible
hinge along a first edge thereof and a frangible coupling along the
remaining edges thereof. When a force is applied to the upper
portion of said openable lid portion, the frangible seal is broken
and the openable lid portion pivots about the hinge. A bottom
surface of the first lid portion includes at least one gripping
element and a bottom surface of the openable lid portion includes
at least one tab element so that when pressure is applied to the
openable lid portion and the openable lid portion pivots about the
hinge, the gripping element engages the tab so as to retain the
openable lid portion in an open disposition.
Other objects, features and characteristics of the present
invention, as well as the methods of operation and functions of the
related elements of the structure, and the combination of parts and
economies of manufacture, will become more apparent upon
consideration of the following detailed description and the
appended claims with reference to the accompanying drawings all of
which form a part of this specification, wherein like reference
numerals designate corresponding parts in the various figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a prior art end closure;
FIG. 2 is a cross-sectional view taken along line 2--2 in FIG.
1;
FIG. 3 is a top plan view of another prior art end closure
embodiment;
FIG. 4 is a cross-sectional view taken along line 4--4 in FIG.
3;
FIG. 5 is an enlarged cross-sectional view of the peripheral edge
of the closure shown in FIG. 4;
FIG. 6 is a bottom plan view of a base from another prior art end
closure embodiment;
FIG. 6A is a top plan view of a rotor;
FIG. 6B is a bottom plan view of the rotor shown in FIG. 6A;
FIG. 7 is a cross-sectional view taken along line 7--7 in FIG.
6;
FIG. 8 is a top plan view of a closure lid provided in accordance
with the present invention;
FIG. 9 is a bottom plan view of an end closure provided in
accordance with the present invention;
FIG. 10 is a cross-sectional view taken along line 10--10 in FIG.
9;
FIG. 11 is a side elevation view, partly in cross section and
partly broken away from clarity showing the interlocking relation
of a tab and a gripping element providing in accordance with the
present invention with the openable lid portion in its open
position;
FIG. 12 is a side elevational view, partly in cross-section and
partly broken away, showing the tab as it moves against the
gripping elements;
FIG. 13 is a side elevation view, partly, in cross section and
partly broken away for clarity showing the openable lid portion its
partially open disposition;
FIG. 14 is a view taken along line 4--4 of FIG. 11 and partly
broken away for clarity;
FIG. 15 is a top plan view of the rotor shown in FIG. 8;
FIG. 16 is a bottom plan view of the rotor shown in FIGS. 8 and
15;
FIG. 17 is a bottom plan view of another embodiment of the present
invention; and
FIG. 18 is a cross-sectional view taken along line 18--18 in FIG.
17.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EXAMPLARY
EMBODIMENT
With reference now to FIG. 8, the top plan view of the end closure
10 provided in accordance with the present invention provides
selective access to the interior of a container.
As can be seen, the end closure 10 includes a bottom or base
generally shown at 12 which includes a substantially planar central
lid portion 13. When constructed and initially placed on a
container (not shown), this portion 13 is integral, it includes no
openings and does not include any opening into the interior to
rotatably support a rotor structure. The base 12 also includes a
peripheral edge 14 which has a lip 15 downwardly therefrom for
engaging a container top edge and for retaining the end closure on
the same. The end closure further includes an upper substantially
planar rotatable lid portion, generally shown at 16, which is snap
mounted on the first lid portion or base 12 so as to be rotatable
relative thereto.
Rotor 16 of the lid 10 includes a semicircular or smile shaped
cutout portion or opening 18 which, as will become more apparent
below, corresponds to the shape of an openable lid or flap portion
20 of base 12. When lid or flap 20 is opened it creates a
semi-circular or smile shaped opening 22. Rotation of the rotatable
portion 16 selectively aligns the cutout 18 with the openable lid
portion 20 and opening 22 to thereby provide access to the
container contents. Similarly, lid portion 16 can be rotated so
that the cutout 18 is not directly aligned with opening 22 to
either vary the size of the opening 22 or to completely close off
the same with the nonperforated, solid area of the rotatable lid
portion 16.
Referring to FIG. 9, the semicircular openable lid portion 20,
provided in accordance with the present invention, can be seen. As
with conventional lids of this type, when this lid portion 20 is
opened, it will produce a pour opening. Initially, however, all
edges of this lid portion 20 are sealed making the closure secure.
Because the planar portion 13 is initially a solid member any
tampering of the closure or any attempt to get into the container
on which the lid is mounted will result in movement of the lid
portion 20. Since any such breach of the sealed edges about portion
20 cannot be repaired, tampering with the closure will be evident.
Also, removal of the rotor 16 will not open the closure.
The edges of lid portion 20 include an arched edge 26, curved end
portion 23 of that arched edge, and a straight edge 24. The
connection between the base 12 and the arched edge 26 and curved
edges 23 is comprised of a solid yet frangible membrane seal 21.
The planar portion 13 of base 12 and lid 20 have a thickness of
about 0.033 inches. The frangible membrane 21 has a thickness of
about 0.003.+-.0.001 inches. The connection, shown at 23, between
base 12 and edge 24 is not frangible but its thickness of about
0.012.+-.0.002 inches allows that connection 23 to operate as a
hinge connection 25 for lid 20, as shown in FIGS. 13 and 14.
Consequently, even after the lid portion 20 has been opened, it
will not fall into the container but will remain a part of the base
12. As mentioned above, the arched edge 26 of the lid portion 20,
as shown in drawing FIG. 9, initially constitutes a frangible seal
so that prior to opening a safe and secure seal is provided to
retain and protect the container contents therewithin but which,
with manual force from the top of the container, can be broken so
as to pivot the openable lid portion 20 about the hinge 25.
The living hinge 25, defined between the openable lid portion 20
and the remainder of the container closure 12, exhibits a degree of
resiliency and thus, after the openable lid portion 20 is opened it
will tend to be disposed at an angle relative to the plane of the
first lid portion 12 as shown for example in FIG. 13. Then, if the
container is inverted or shaken to remove some material from within
the same, the material can contact the angularly disposed openable
lid portion 20 and push the lid into a closed or semi-closed
condition. Thus, the openable lid portion 20 can disadvantageously
interfere with removing contents from the container.
In order to avoid such interference, in accordance with the present
invention, at least one tab element, designated generally at 28, is
provided on the bottom surface of base 12 and specifically on he
bottom of lid 20. Preferably two tab elements are provided, with
one tab element at each longitudinal end of the living hinge 25
with both provided on the under surface of the openable lid portion
20. Further, gripping elements or retainers, generally shown at 30,
are provided on the bottom portion of the base 12 adjacent but on
the opposite side the living hinge 25 from tabs 28. The gripping
elements 30 include a substantially vertically disposed wall
portion 32 and an overhanging flange portion designated generally
as 44.
The tabs 28 are comprised of an upstanding wall section 36 having a
height sufficient to extend under flange 34 when the lid 20 is
opened as shown in FIG. 14. The precise length of wall 36 is not
critical so long as it can engage and be retained by flange 34.
Tabs 28 also include a reinforcing member 38 in the form of a
triangular wall extending between lid 20 and wall 36. As shown in
FIG. 11, each wall 36 includes an inboard side 40 and an outboard
side 42, the latter being the side that moves past flange 34. Side
42 can also have sliding contact with vertical wall 32. It should
be noted that the reinforcing member 38 is positioned closer to
inboard side 40 than side 42 so that, as shown in FIG. 12, as lid
20 is opened wall portion 36 can move or be deflected as side 42
contacts flange 34. Once side 42 clears flange 34 it will snap
under that flange into the position shown in FIGS. 11 and 14 and be
retained in that position. The reinforcing member 38 provides the
proper amount of stiffness to wall 36 making it not so stiff it
will resist bending movement yet stiff enough to provide a suitable
retaining force for lid 20 under flange 34.
With reference again to FIG. 11, side 42 is itself comprised of an
upper portion 44 that can be either flat or slightly radiused and a
lower portion 46 that is beveled or angled from the end of the
portion 44 to the opposite face.
It should also be noted that flange 34 does not extend across the
full width of wall 32. Rather, as shown in FIG. 13, flange 34
extends across about three quarters of the width of wall 32 toward
lid 20 leaving a portion of wall 32, designated generally, at 48,
free of the flange. This provides additional turning radius for
wall 36 as lid 20 is rotated toward its full open position and aids
in allowing lid 20 to be easily opened, allows wall 32 to help
guide side 42 of wall 36 as it is deflected by flange 34 and allows
the lid 20 to be raised into a better angular position with respect
to the gripping element 30 to thereby gain the leverage needed to
effect the retaining and snapping movement. The beveled portion 46
also aids in developing the desired opening, eases the retaining
process and permits a stiffer flange than might otherwise be
possible.
Thus, as the openable lid portion 20 is pivoted to its open
position as shown in FIG. 13 to its fully open portion as shown in
FIG. 14, the tab elements 20, defined on the longitudinal edges of
the living hinge 25 the openable lid portion 20, will engage and be
deflected by or snap past the overhanging portion 34 of the
gripping member 30. Once the tabs 28 are snapped past the gripping
members 30 and the pressure on the openable lid portion 20 is
released, it will be held in open position as shown in FIGS. 11 and
14 by the overhanging portion 34 of the gripping element 30. If
desired, the openable lid portion 20 can be released from the
gripping members 30 by applying a force tending to pivot it about
its living hinge 25 towards the closed disposition. However, absent
such positive manual force, the openable lid portion 20 will be
retained in its open configuration and will not be "unlocked" by
dispensing powdered material and the like from within the
container, even if the can is inverted and shaken.
With specific reference to FIG. 10, which is a cross-section of
base 12 and rotor 16, the depending flange 14 is shown as having a
tapered or beveled outer surface 31 that extends around the entire
periphery of the base to help ease the closure into a container. A
series of ribs, one of which is shown at 33, also extend around the
depending flange 14 to assist in providing a proper interference
fit and to provide additional surfaces for gluing or otherwise
attaching the base to a container. The exterior sidewall terminates
in an inverted V-shaped slot 35 into which the peripheral end of a
container can fit or partially fit depending upon the sidewall
thickness of the container. The top surface of the base, as shown
in FIG. 10, includes an outer flat ledge 37 that also extends
around the entire periphery of the upper surface of the end
closure. This provides a surface that can be engaged by the end
closure positioning apparatus to help force the closure into a
container. In addition, this together with a raised rib structure,
generally indicated at 39, provides a way of stacking individual
ends as well as containers once the bottom is placed in the
container. The front surface of the raised portion 39 is defined by
a sloped wall 41 which terminates at a horizontally extending
flange 43. Representative dimensions for an end closure designed
for an 8 ounce container would provide a flange that is preferably
about 1.375 inches in width, about 0.15 inches in height and its
upper surface is positioned approximately 0.68 inches from the top
of planar surface 45 of the central portion of base 12. Surface 45,
as shown in FIG. 10, extends across the top of base 12 and includes
no other openings other than that which will ultimately be defined
when lid portion 20 is opened.
The portion of the base 12 lying beneath flange 43 is comprised of
a vertical wall 47 which flows into a radius groove 49 which then
flows directly into the planar surface 45. In a closure for an
eight ounce container the radius portions of groove 49 will
preferably be about 0.0325 inches and a 0.032 inch flattened area
can be provided in the center, as indicated at 51.
FIGS. 15 and 16 show rotor 16 according to this embodiment of the
present invention. The peripheral portion of both the rotor and
base as mounted together is shown in FIG. 10.
Turning first to FIG. 15, the rotor 16 is provided with a top
surface 60 while its bottom surface 62 is shown in FIG. 16. As
noted above, rotor 16 is also provided with a semi-circular or
smile type cutout area or opening 18 and a handle member is
provided on the top surface such as shown at 64. Handle 64 can be
in the form of two separate pieces as shown or one continuous
piece. Other shaped handles could also be employed since all that
is necessary is that some raised means be provided to turn the
rotor 16 relative to the base 12 as indicated by the double arrow
shown in FIG. 8.
FIG. 10 is a cross-section of the closure 10 and shows the inner
fitting relationship between the rotor 16 and base 12. The marginal
edge of rotor 16 has been designed with some specific purposes in
mind. Concentrating first on the upper surface 60, the outer
periphery includes a substantially flat ledge 66 and inboard from
that is a rounded annular rib 68. The outer periphery is defined by
a sloping sidewall 70 which has about a 10.degree. slope with
sidewall 70 then flowing into an annular ring 72 forming the
exterior base of rotor 16. Elements 66-72 can be referred to
collectively as a locking ring which is generally designated at 74.
As shown in FIG. 10, this locking ring structure 74 fits within
base 12 with flange 43 overlying the flat area 66 and with the
radius portion 72, which can also include a flattened lower bottom
area, lying within the radiused area generally indicated at 49 and
51. The raised rib 68 lies just outside the front edge of flange
43. This not only assures that the rotor 16 is positively held and
retained within the base 12, so that it can rotate easily, but the
flange 43 provides a seal between the rotor and base both with
respect to its bottom surface and the flattened surface 66 on the
rotor and also because of the close positioning between the outer
edge of flange 43 and rib 68. Additionally, the composite
peripheral edge structure of the rotor also helps maintain the
flat, planar configuration of the rotor which is important with
respect to maintaining a proper seal between rotor 16 and the
planar surface 45 of the base.
In an effort to further improve that sealing capability of the
rotor, an additional rib 76 is provided on the bottom surface 62 of
the rotor relative to surface 45, as shown in FIGS. 10 and 16. Rib
76 extends about the entire periphery of the opening 18 and as in
FIG. 10, with opening 18 aligned with lid portion 20, and thus
opening 22, rib 76 engages surface 45 about opening 22.
Accordingly, the peripheral edge area of rotor 16 along the arched
edge of opening 18 is comprised of two adjacent but slightly
separated ribs, one being the outer peripheral edge 72, the other
being the inner ridge 76. This double rib structure also
strengthens the otherwise thin portion of the rotor surrounding the
curved portion of opening 18 and also holds the rotor flat. In a
frame closure, rib 76 has a depth of approximately 0.020 inches
with the outer rib 72 having a depth of about 0.025 inches. The
slightly lower depth for rib 76 assures that rib 76 will contact
surface 45 and that rib 72 lies completely within its mating groove
in base 12. Consequently, the peripheral portion of the rotor
extending around opening 18 has a sliding contact with the planar
surface 45 of the base. Thus, when the opening 18 is positioned in
an aligned fashion over the opening defined by lid 20, rib 76 will
be in contact with the portion of surface 45 extending about the
opening performed when lid 20 is opened so that upon the pouring of
contents from any container containing this closure, rib 76 will
provide a seal between the rotor and the base. Material will not
flow between the rotor and base. In addition, rib 76 provides
additional reinforcing and structural support in rotor 16 about the
opening 18.
As rotor 16 is rotated out of alignment with the opening in the
base formed when lid portion 20 is open, rib 76 will slide on
surface 45 and in a closed position rib 76 rests upon the remaining
solid surface portion of the base and continue to remain in sliding
contact with surface 45. This assists again in maintaining the flat
planar relationship that is desired for the rotor, it helps
maintain the seal around the periphery of the rotor between the
rotor and the base and also provides a continuing seal about
opening 18. This helps maintain freshness of the contents in the
container, protects the contents from outside influences and
assures that material from within the container will not spill out.
In short, rib 76 helps prevent contamination, following opening, of
the contents in the container.
Another embodiment of the present invention as set forth in FIGS.
17 and 18 is comprised of a similar rotor. However, in lieu of the
tabs 28 and the retainers 30, a single depending projection 80 is
provided on the bottom surface 82 of the base 84 and two depending
members 86 and 88, which are spaced apart a distance slightly less
than the width of member 80. Members 86 and 88 are positioned on
the flap, as shown in FIG. 17 so that when the flap 90 is opened,
as shown in FIG. 18, the pair of members 86 and 88 will
frictionally engage and be retained by member 80, thereby holding
lid 90 in an open position as shown in dotted lines in FIG. 20.
While one pair of members 86 and 88 and one retainer 80 are
provided on the bottom surface of the lid and base, respectively,
another set of these elements could also be provided with the two
sets being positioned adjacent the ends of the lid as is the case
with tabs 28 and gripping elements 30 in the first embodiment.
As is apparent from the foregoing, the present invention provides a
simple yet advantageous means for retaining the openable lid
portion in its open disposition thereby preventing such a hingedly
connected lid portion from interfering with access to the container
contents.
While the invention has been described in connection with what is
presently considered to be the most practical and preferred
embodiment, it is to be understood that the invention is not
limited to the disclosed embodiment, but, on the contrary, is
intended to cover various modifications and equivalent arrangements
included within the spirit and scope of the appended claims.
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