U.S. patent number 3,756,480 [Application Number 05/122,437] was granted by the patent office on 1973-09-04 for three-part press type seal.
This patent grant is currently assigned to Dart Industries, Inc.. Invention is credited to Jack V. Croyle, James B. Swett.
United States Patent |
3,756,480 |
Swett , et al. |
September 4, 1973 |
THREE-PART PRESS TYPE SEAL
Abstract
A multi-part and distortable seal construction employing a
biased center wall and sealing wall arrangement which, upon the
application and release of pressure to a center-positioned plunger,
distends and contracts the sealing wall portion thereof.
Inventors: |
Swett; James B. (Barrington,
RI), Croyle; Jack V. (Woonsocket, RI) |
Assignee: |
Dart Industries, Inc. (Los
Angeles, CA)
|
Family
ID: |
22402711 |
Appl.
No.: |
05/122,437 |
Filed: |
March 9, 1971 |
Current U.S.
Class: |
222/484; 220/234;
222/563; 220/305 |
Current CPC
Class: |
B65D
39/12 (20130101); B65D 43/022 (20130101); B65D
2543/00092 (20130101); B65D 2543/00296 (20130101); B65D
2543/00888 (20130101); B65D 2543/00231 (20130101); B65D
2543/00546 (20130101); B65D 2543/00407 (20130101); B65D
2543/0049 (20130101); B65D 2543/0037 (20130101) |
Current International
Class: |
B65D
39/12 (20060101); B65D 43/02 (20060101); B65D
39/00 (20060101); B65d 047/14 (); B67d
003/00 () |
Field of
Search: |
;222/563,479,481,482,484,518,552,554,559,561,522,495 ;215/52
;220/24.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Reeves; Robert B.
Assistant Examiner: Bartuska; Francis J.
Claims
We claim:
1. A locally distortable closure member contractably and
distensibly constructed and having an elastic memory such that it
is adapted to hermetically seal an open-mouthed container and
comprising:
a. a center main wall including a biased area radially emanating
from a central portion thereof to a peripheral terminus, said
center main wall being adapted for the application of pressure to
the approximate center thereof in such manner that said biased area
tends to collapse upon itself and substantially uniformly displace
said peripheral terminus until said closure is easily positionable
in an open-mouthed container;
b. integral extended sealing means positioned around said
peripheral terminus of the center main wall, said sealing means
being displaceable in like manner with said peripheral terminus
such that at least a portion of said sealing means is closely
engageable with and sealable against the walls of an open-mouthed
container due to the resiliency and elastic memory of said closure
upon the discontinuance of applied pressure to said center main
wall;
c. a closure top wall interconnected with said integral extended
sealing means and said center main wall, said closure top wall
further including an integral and substantially centered upstanding
bushing-like guide terminating at its upper extremity in a finger
grippable flange; and,
d. an axially movable plunger positioned in said guide in such
manner as to have a portion thereof exposed above said flange so
that pressure applied to the plunger is transmitted to the
approximate center of said center main wall.
2. A closure member according to claim 1 wherein said plunger is
secured to said center wall at the approximate center thereof.
3. In combination a container and a removable closure member
according to claim 1 wherein said container includes a projecting
wall construction forming the open mouth thereof and including
therein a pouring spout and venting slot approximately opposite one
another, said projecting wall construction being so that said
removable closure is engageable with and sealable thereagainst
below said spout and slot and is engageable and sealable with
portions of said wall at positions proximate said spout and slot so
that with the removable closure in the latter mentioned positions
the container contents may be easily poured therefrom.
4. The combination according to claim 3 wherein said projecting
wall also includes inwardly protruding means removed from the upper
edge of said container such that said portion of the sealing means
is positionable therebetween, said protruding means further
providing an abutable surface against which said closure is
positionable to assure its proper placement within the
container.
5. A closure member according to claim 1 wherein the closure top
wall and the integral extended sealing means include opposed
locking means interconnectably overlapping to secure said top and
main walls together.
Description
This invention relates to containers and container closures in
which the closures are formed from distortable materials of
construction. More particularly, the invention concerns
distortable, reusable, plastic container closures for open-mouthed
containers and further contemplates a closure arrangement that is
quickly and easily operable and which assures a reliable hermetic
seal.
Plastic food storage containers have been available for many years
and have generally employed a bowl, cylinder, pitcher or similarly
shaped vessel and a separate closure or lid made of a relatively
flexible material. Further, the closures have normally been of
several types, one of which includes an inverted peripheral groove
that is placed upon the top edge or rim of a container wall and is
pressed onto or expanded over that edge to form a hermetic seal
between the two parts. Another typical closure is the two-position
type which may be flexed to either of two fixed positions. In one
of these positions, the closure may be easily fitted over the rim
or within the open-mouth of a container, and then when flexed to
the second position, its peripheral portions are forced into tight
locking contact with the rim or inside container wall. Others
include the cork-like and toggle-like closures which loosely fit
into the open mouth of a container and which are thereafter
expanded into contact with the container inside wall surfaces.
Then, of course, there have been the relatively inflexible plug
type closures that have been provided for these purposes. Normally,
these have been employed with vessels that are also relatively
inflexible and include a tapered body portion into which the
closure could be inserted until it frictionally engaged the tapered
body.
As might be expected, all of the mentioned closures have been quite
satisfactory in operation and construction. It should be noted,
however, that each is not wholly satisfactory from a plurality of
diversified points of view. For example, the closure having the
inverted peripheral groove has had to be stretched over or pressed
onto the container rim normally by finger pressure applied at
successively adjacent points along the top groove defining wall.
This, of course, may be a time-consuming and laborious procedure,
especially if the closure is as tight fitting as is required to
obtain a hermetic seal. Further, when the closure must be stretched
in this manner, stress concentrations are increased to such a
degree that stress cracking may result. Similarly, lids of this
type are susceptible to warpage due to the inordinate internal
stresses and in this warped condition, placement of the lid on a
container is made more difficult and sometimes even impossible.
The two-position closure may also require some dexterity if it is
to be accurately locked in position. When using this closure, the
peripheral edge of the closure must be maintained in close
association with the top edge of the container as the top wall of
the closure is flexed to its locking position. As might be
expected, this, in some instances, necessitates that the closure be
simultaneously held at the edges and flexed at the center.
Similarly, the toggle-action closures may also require dexterity in
their proper assemblage with suitable closures. In addition,
however, the toggle action lids include hinged areas that
necessarily have been weakened and are therefore more susceptible
to failure. These also present numerous molding difficulties which
tend to limit the materials of construction from which they may be
manufactured. And, of course, like the tightly stretched closure
mentioned above, extreme stresses are created in the sealed
position and this accelerates stress cracking of the closure.
Further, if a roll-type toggle is employed, it is not uncommon for
the seal between the closure and container to be lost if items are
placed on top of the closure so that the weight of such items
depresses the dome-like central area thereof. It should also be
apparent that such closures also have a tendency to turn
inside-out, thus requiring that the user reinvert the closure
before any further attempt is made to seal the container.
The expandible cork-like closures are also deficient in several
respects, especially where large open-mouthed containers are
concerned. For example, the construction of such closures besides
employing complicated mechanical manipulative devices also
necessarily decrease the usable volume in where they are used
because of their bulk. Likewise, the plug type closures lack
versatility and, of course, are somewhat unreliable in their
sealing action.
This invention provides a sealing closure that is, in all respects,
representative of a composite incorporating the good features of
those mentioned above, and in addition, is more simple in its mode
of operation. The construction more fully described hereinbelow
enables the user to apply the closure of this invention to any of
several types of containers simply by an application of pressure to
the approximate center of the closure main wall. As is readily
discernible from the drawings, this closure is of a multi-pieced
construction and includes a finger operable plunger that is adapted
to transmit pressure to the approximate center of the main
wall.
This new closure further includes several distinctive
constructional features which enhance its applicability for use in
a food storage capavity as well as in other related fields. Among
these is a biased, corrugated, fluted or similar center main wall
arrangement that effectively and easily enables the contraction and
recovery of the center main wall peripheral edge to a relaxed or
as-molded posiltion. This edge, of course, includes as an integral
part a sealing wall portion which functions to produce a sealed
relationship between closure and container, thus preserving and
physically retaining the contained materials therein.
The invention also encompasess variable construction parameters
affecting the efficient operability of such closures. Therefore,
the construction described in detail below has as its principle
objectives to minimize both internal stresses within the closure
and the force required to properly assemble a closure and
container, while at the same time to maximize the sealing pressure
between the closure and container and the lateral contraction of
the closure sealing wall portion per unit of applied force. In
these respects, it is applicant's wish that the disclosures in
co-pending U.S. patent applications Ser. Nos. 8,228, now U.S. Pat.
No. 3,679,088 and 67,340, now U.S. Pat. No. 3,679,089 filed on Feb.
3, 1970, and Aug. 27, 1970, respectively, be incorporated by
reference in this application for Letters Patent.
Further objectives of the invention, of course, are to provide: an
improved closure that is easily applicable to a container and yet
will effectively hermetically seal that container; a closure
construction which may be molded by compression or injection
techniques and which will be economical to manufacture and durable
in operation.
Other objectives and advantages will becomd more apparent upon
further reference to the specification, drawing and claims which
describe the invention in more detail and wherein:
FIG. 1 is a top view of a closure construction incorporating the
concepts of this invention;
FIG. 2 is an enlarged cross-section of the closure and a partial
cross-section of a pitcher, the closure cross-section being taken
along line 2--2 in FIG. 3 and showing the closure in sealing
relationship with the container;
FIG. 3 is a bottom view of the closure as is depicted in FIG.
1;
FIG. 4 is a partial cross-section of a typical closure of this
invention and of another container; and,
FIG. 5 is a partial cross-section of a pitcher adapted to
accommodate the closure of this invention.
Referring now to FIGS. 1-4, it can be seen that the closure member
10 of this invention is composed of a plurality of separate parts
which function together in the operation of the closure. These
include a radially biased, fluted or corrugated center main wall 14
having a centrally positioned substantially planar area 16 in the
center surface wall and an upwardly extended side wall 26; a
closure top wall 12 having an integral substantially centered
bushing-like guide 13; and a plunger 15. Specifically, the biased
or corrugated areas are composed of a plurality of upstanding
tapered ridges 18, more fully described hereinafter, which emanate
from the substantially planar area 16 and terminate at the
peripheral edge 24 of the center main wall 14.
The closure center main wall 14 is preferably formed from a
distortable thermoplastic, for example, low density polyethylene;
however, high density polyethylene, polypropylene, polyolefin
blends or similar materials, even light gage metals may be suitably
employed using the inventive concept. Likewise, the open-mouthed
containers 20 (FIGS. 2 and 4) with which these closures are
primarily intended for use, are also generally formed from the same
or similar materials. It should be pointed out, however, that such
closures may well be adapted for use with containers of a
diversified range of materials such as glass, metal, etc.
Upon continued reference to FIGS. 2 and 4, it can be seen that at
the peripheral edge 24 of the center main wall, there is an
integral upwardly extended side wall 26. The outer portion 28 of
wall 26 is adapted for mating engagement with the inner area of the
projecting wall 30 which forms the open mouth in container or
pitcher 10. This engagement, of course, creates the hermetic seal
spoken of and thus produces a highly desirable storage container
especially suited for the storage of foodstuffs and/or liquids.
These closure embodiments include an outwardly protruding bead 32
which extends around the periphery of outer portion 28 of wall 26
which bead presses against the container walls in sealing
relationship with them. FIG. 2 further shows a circumferential
ledge 34 which is intended to act as a bottom stop member for the
closure 10. As is readily apparent, the ledge is produced by
downwardly directed inwardly sloping portion 36 of the pitcher wall
21. This terminates after a relatively short inward progression and
the normal inner wall contour is resumed. This ledge tends to
assist the user in the proper orientation of the closure on the
container; however, as is evident from FIG. 4, containers of other
configurations may similarly employ this closure member. In fact,
this type of closure may be used to "chase" a diminishing amount of
foodstuff or liquid down into the container. This operation would
minimize the amount of air trapped in contact with the remaining
foodstuff in the container and thereby lengthen the time of
preservation of the remaining contents.
Again with particular reference to the pitcher 20 in FIGS. 2 and 5,
note that a small interrupted bead 23 partially extends around the
inside of wall 21, adjacent the upper edge 27 of the pitcher. This
bead functions as an upper stop or position indicator so that the
user may accurately reposition the closure 10 immediately below
this bead. In this elevated position, the closure will not contact
the wall 21 in the area of pour spout 25. Therefore, the closure 10
will remain securely engaged with the pitcher, yet pour spout 25
will be open to the container interior enabling the easy discharge
of fluids or the like while the closure is so attached. To assist
in this discharge, note that a tapered venting slot 17 is provided
on the inside surface of wall 30 approximately opposite pour spout
25 so that when the closure is positioned in its elevated position,
air may be bled into the pitcher at that point. For complete
sealing of the pitcher 20, however, it is only necessary to again
reposition the closure adjacent ledge 34 which is below the pour
spout 25. Thus, sealing will be effected all around the pitcher 20
between protruding bead 32 and wall 21.
Referring now to FIG. 3, in particular, one will recognize that in
operation the locally distortable closure member is contractably
and distensibly constructed so that the wall 26 will be displacible
with the peripheral edge 24 of biased center main wall 14. In
accomplishing this, the resiliency and elastic memory of the
particular materials of construction must be considered and, in
particular, the center main wall shape should be carefully
constructed to take advantage of the physical characteristics of
the materials employed. Therefore, the radially extending biased
center main wall 14 which extends between the center portion or
substantially planar area 16 to a peripheral terminus 24 is of
considerable importance to the invention. In essence, the biased
center main wall 14 tends to collapse upon itself upon the
application of pressure to center portion 16. This collapse
substantially uniformly displaces the peripheral terminus 24
inwardly and thus draws the wall 26 inwardly.
The biased, corrugated, fluted or plaited center main wall 14
includes, therefore, a plurality of upwardly and outwardly tapered
ridges 18. As can be readily seen in FIGS. 2, 3 and 4, the upper
portion 38 of these ridges are angularly directed with respect to
planar area 16 and therefore their respective peripheral terminus
portions 24 lie plane removed from that of area 16. Similarly, the
bottom portions 40 of these plaits lie in a substantially parallel
plane approximate to that of area 16 when the closure is in a
relaxed or as-molded condition. However, when the closure is in
place upon a container, even the bottom portions 40 will be at
least slightly angularly directed toward the container center; such
being the result of oversizing which assures a proper seal between
the components.
The corrugation height at its peripheral terminus 24, i.e., the
point of connection to the integral upwardly extended side wall 26,
is such that the uppermost flute portion 38 is approximately
opposite or above the protruding bead 32. Thus, even through the
lateral dimensions of the outer portion 28 at bead 32 are slightly
greater than that of the inside diameter of the container, the
application of pressure to the centrally positioned substantially
planar area 16 will cause sufficient inward lateral displacement of
the side wall 26 such that the closure slips easily onto the
container.
As is best apparent from FIG. 2, the side wall 26 also includes a
plurality of inwardly and upwardly disposed projections 29 which
are integrally molded at spaced points around the wall. These
projections 29 terminate at points adjacent the upper edge 35 of
the wall and below the inwardly directed undercut 37 that is formed
at the upper edge. Similarly, the socket 39 framed by wall 41
projects upwardly from the planar area 16 such that it cooperates
with the plunger 15 as is described hereinbelow.
The closure top wall 12 includes a conically disposed upper wall 38
in the approximate center of which there is positioned the
bushing-like guide 13. This guide extends above the upper wall 38
and is aligned with the socket 39. A peripherally disposed
depending skirt 40 is positioned adjacent the outermost periphery
of upper wall 38 so as to create a lip 42 around the periphery
thereof. This lip then is positioned between the undercut 32 and
terminal points of projections 29 and is securely held therebetween
by these elements.
The plunger 15 is, of course, received in the bushing-like guide 13
for axial movement therein and is further received by the socket
39. The socket further includes a plurality of inwardly extending
ribs 44 which pressingly engage the plunger and secure it in the
socket and to the center main wall 14. As is apparent, plunger 15
also includes a ledge area 47 intermediate of its extremities which
ledge area is adapted to engage with the undersurface of wall 38
adjacent bushing 13 and to thereby function as a stop to arrest the
upward movement of the plunger and center main wall 14. Thus,
axially applied pressure is transmitted by the plunger 15 to the
planar area 16 of the center main wall 14 and the displacement of
peripheral terminus 24 of wall 26 results as discussed above. The
upper portion of guide 13 also includes a finger-grippable flange
45 above which the plunger is adapted to protrude. Thus, in
operation the guide may be gripped between the finger digits below
flange 45 while the plunger is depressed with the thumb, creating
the axial pressure spoken of.
As was mentioned, one prime objective of this invention is to
optimize forces for applying closures, sealing pressures and
stresses but at the same time, to obtain a maximum of sealing
pressure using minimum force and creating minimum stresses.
Therefore, analysis of the relationships between the applied axial
force (push-down pressure), the lateral contraction or displacement
of the side wall 26, the stresses within the closure, and the
sealing pressure becomes significant and a discussion of thee may
be found in U.S. Ser. No. 8,228 and 67,340, filed on Feb. 3, 1970,
and Aug. 27, 1970, respectively.
It should be obvious that other similar top wall and plunger
constructions may be employed in carrying out the invention. For
example, a sleeve and plunger might be suitably inserted and
retained within the bushing-like guide in such manner as to permit
elimination of the socket 39. Similarly, the plunger might be made
integral with the center main wall 14 thereby reducing the number
of separate parts included in the construction.
In operation, the closures of this invention tend to experience a
lateral displacement within the conical, corrugated or fluted area
18 as pressure is applied to the planar area 16. The conical
corrugated construction accentuates this displacement as the flutes
fold upon themselves in an accordion-like fashion. This, then,
similarly tends to draw the side wall 26 inwardly, thereby
facilitating entry of the central surface wall area 14 into the
open-mouth end of the container or pitcher 20. After insertion and
upon release of the applied pressure, the resilient closure
material attempts to assume its relaxed orientation and thus
expands the side wall 26 against the inner portion of the container
wall to hermetically seal the container. To remove the closure, it
is only necessary to similarly depress the plunger 15 to remove the
closure from the pitcher or container.
From the foregoing description, it should be apparent that the
invention encompasses an advantageous advance in the art. Further,
it should be clear that the invention may be embodied in other
specific forms without departing from the spirit of the essential
characteristics thereof. The present embodiments are, therefore, to
be considered in all respects as illustrative and not
restrictive.
* * * * *