U.S. patent number 3,904,072 [Application Number 05/355,831] was granted by the patent office on 1975-09-09 for screw on lid.
This patent grant is currently assigned to Continental Can Company, Inc.. Invention is credited to Robert C. Whiteside.
United States Patent |
3,904,072 |
Whiteside |
September 9, 1975 |
Screw on lid
Abstract
A cup lid adapted to thread onto a container which is made of a
soft cushion material such as expanded polystyrene. The lid has a
downwardly open channel or groove on its outer margin. Outward
threads are formed along the inner wall of the open channel to
allow the cup lid to be threaded into a cup.
Inventors: |
Whiteside; Robert C.
(Plainwell, MI) |
Assignee: |
Continental Can Company, Inc.
(New York, NY)
|
Family
ID: |
23399009 |
Appl.
No.: |
05/355,831 |
Filed: |
April 30, 1973 |
Current U.S.
Class: |
220/288;
229/906.1; 229/125.24 |
Current CPC
Class: |
B65D
81/3867 (20130101); B65D 43/0229 (20130101); B65D
2543/00398 (20130101); B65D 2543/00842 (20130101); B65D
2543/00509 (20130101); B65D 2543/00555 (20130101); B65D
2543/00296 (20130101); B65D 2543/00537 (20130101); B65D
2543/00092 (20130101); B65D 2543/00574 (20130101) |
Current International
Class: |
B65D
43/02 (20060101); B65D 81/38 (20060101); B65D
043/04 () |
Field of
Search: |
;220/27,42R,42A,6R,288,306,352,355,39R ;229/43 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Price; William I.
Assistant Examiner: Hart; R. E.
Attorney, Agent or Firm: Lockwood, Dewey, Zickert &
Alex
Claims
I claim:
1. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material, said lid
comprising:
a central section of such size as to extend substantially across
the mouth of the container;
means defining a downwardly opening circumferentially extending
cavity on said lid and attached to said central section and having
inner and outer walls;
and
at least one thread formed on the inner wall of said cavity and
inclined to the horizontal axis of the lid whereby as the lid is
rotated onto the container said thread cuts into the inner side of
said rim to form a detent to hold the lid onto said container.
2. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material as set forth
in claim 1, said downwardly extending circumferential cavity means
comprising:
a continuous skirt forming the outer wall of said cavity;
a series of triangular segments forming the inner wall of said
cavity;
a circumferential connecting wall connecting said skirt to one side
of each of said series of triangular segments; and
at least one thread formed on each of said series of triangular
segments whereby said thread engages said soft cushioned material
to hold said lid on said container.
3. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material as set forth
in claim 1 in which said central section comprises:
a central panel;
indents formed adjacent said central panel and each comprising:
an indent outer wall formed by a segment of the inner wall of said
cavity;
an indent inner wall attached to an outer edge of said central
panel; and
a plurality of wings extending from said central panel to connect
with the top of said circumferentially extending cavity and having
a margin of each said indent attached to a second side of said
wing.
4. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material as set forth
in claim 3
wherein said indent outer wall is generally triangular, and
wherein each said indents further include a generally triangular
panel having:
a first side connected to the lower edge of said indent outer
wall;
a second side connected to the lower edge of said indent inner
wall; and
a third side connected to the side of said wing which is opposite
to the side wall connected to said indent inner wall.
5. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material as set forth
in claim 3 in which said central panel
is rectangularly shaped.
6. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material as set forth
in claim 2 in which said circumferential connecting wall
comprises:
a flat ring.
7. A lid for threading engagement with a container having a rim
forming a mouth and made of a soft cushioned material as set forth
in claim 6 comprising further:
radial knurling extending around said flat ring to provide lateral
stiffening to said annular ring.
8. A closure cap for threadingly holding a lid onto a container
having a rim forming a mouth and made of a soft cushioned material,
said lid comprising:
a central section extending substantially across the mouth;
means defining a downwardly opening circumferentially extending
cavity on said lid and attached to said central section;
an outer wall forming the outer part of said cavity;
wall sections connected to said central section and forming the
inner wall of said cavity;
a connecting wall between the upper part of said outer wall and
said inner wall sections; and
an external screw thread formed on the inner wall of each said
inner wall section whereby said lid is threaded into said rim of
said containers.
9. A closure cap for threadingly holding a lid onto a container
having a rim forming a mouth and made of a soft cushioned material
as set forth in claim 8 in which said central section
comprises:
a central panel of a generally rectangular shape;
wing panels having one edge attached to said central panel and the
opposing edge attached to said connecting wall;
curved triangular panels forming said wall sections and having a
top side connecting to said connecting wall;
indents formed adjacent said central panel;
a generally triangular panel forming the bottom of each said indent
and having:
a curved side connected to the bottom of said curved triangular
panel;
a side connected to an edge of said wing panel; and
an indent inner wall connected to an upper edge of a wing panel and
a lower edge connected to a straight side of said generally
triangular panel.
10. A lid for a container having a rim forming a mouth, said lid
comprising:
a central section of such size as to extend substantially across
the mouth of the container:
means defining a downwardly opening circumferentially extending
cavity on said lid attached to said central section;
and
at least one screw thread formed on the inner part of said cavity
such as to press into the rim of the container to form a detent to
hold the lid onto said container.
Description
My invention relates to cup lids and particularly to a cup lid for
closing a container made of a soft cushion material.
In the manufacture of cups and other containers made of soft
cushion material such as expanded polystyrene or expanded
polyurethane and a similar material, the cups which are supposed to
be of the same size are often of slightly differing sizes because
of different conditions of manufacture or because of some variants
in the substance used in the cup. For one reason or another, the
diameter of the cup lip and thickness varies somewhat from cup to
cup. For this reason, snap-on lids frequently fail to grip the cup
lip and thus fall off of the cup. In short, sizing containers to
close tolerances is very difficult and is infrequently done. Thus,
the lip of the mouth of the cup varies in size and may or may not
form a close fit with a snap-on lid because the outside diameter of
a snap-on lid is made to close tolerances.
In the past, snap-on lids have been used to seal the open mouths of
cups made of soft cushion material. However, as indicated above
this system has frequently been ineffective and resulted in spilled
liquid with burning or staining resulting. These containers are
usually filled with hot liquids and the expanded material is used
for its insulating qualities as well as its strength.
It is an object of this invention to provide a lid which threads
into the mouth of a cup which is made of a soft cushion
material.
It is another object of this invention to provide a lid which fits
a cup made of soft cushion material and allows the lid to thread
onto the cup even though the dimensions of the cups. of the same
manufactured size, vary some in height, thickness and diameter from
cup to cup.
Other objects and advantages of the invention will become apparent
from the detailed description taken in connection with the
accompanying drawings in which:
FIG. 1 is a perspective view of the lid with a section cut
away;
FIG. 2 is a top view of the lid showing knurling and internal
bracing;
FIG. 3 shows the lid turned onto a cup with a section of the lid
and cup broken away showing the threads on the inner wall of the
downwardly open groove.
The lid 1 shown in FIG. 1 is made of a thin plastic material to fit
as a cap or lid on the top of a container 2 of expanded
polystyrene, expanded polyurethane or made of other soft cushioned
material. The container is not shown in FIG. 1 but the assembly of
the container cap 1 on a container 2 made of expanded polystyrene
or the like is shown in FIG. 3 with a cutaway section to show the
thickness of the container. The lid has a central section 3 of a
generally circular configuration. Extending around the periphery 4
of the central section 3 is a downwardly opening circumferentially
extending cavity or channel 5. The channel 5 has as its outer wall
6 a somewhat conically shaped skirt 7. The outer wall 6 may
actually be shaped as having a lower curvilinear skirt 7 with a
circumferential straight side wall 8 above it or may be shaped into
a truncated right circular cone or cylinder (not shown). The
circumferential straight side wall 8 connects the external skirt to
a top connecting ring of the channel. As shown in FIG. 1, the inner
wall 9 is formed by a series of curved triangular panels 10. Only
four such triangular panels 10 are shown in FIGS. 1-3. Actually,
any number of panels may be used depending on the size of the lid
and the thickness of the material of the cup lid. For the ordinary
typical small size cup and cup cover, four panels 10 are found to
be an optimum number.
A screw thread 11 is formed into the surface of each triangular
panel. The thread 11 extends at an acute angle to the plane of the
top of the lid. The bearing surfaces 12 of the threads 11 are
external and project into the channel. A convenient place for the
thread is along the bottom of the triangular panel 10 as shown. In
this way, when the lid 1 is turned onto the expanded polystyrene
cup 2, the cup lid 1 is threaded into the soft cup wall 2. After
being threaded, the cup lid 1 occupies a position as shown in FIG.
3. The threads 11 on the curved triangular panels 10 and the panels
10 themselves are each braced to some extent by an indent bracing
panel 13 which extends inwardly from the curved triangular inner
wall 10. A bracing panel 13 extends inwardly from the lower edge of
each triangular panel 10 of the inner wall until it comes to the
indent inner wall 14. The flat section of the bracing panel 13
which is shown in FIGS. 1 and 2 serves to hold the thread 11 on the
inner wall 10 against the soft cushioned material of the container
2. The thread 11 as it is turned against the container 2 threads
the container 2 and may even to a slight extent cut the soft inner
wall 15 of the cushioned material as it threads down into the mouth
of the container. The closure cap 1 is pulled downwardly and the
container wall 16 is pressed somewhat outwardly against the skirt 7
and outer wall 8 of the downwardly opening channel 5. As the side
of the container presses against the outer wall 8 of the channel 5,
it is forced somewhat inwardly against the threading 11. This
process makes the cap 1 more securely tightened onto the inner wall
10 of the container. The upper edge 17 of the container wall 16
finally comes up against the top connecting ring 18 which is shown
with knurling 20 along its upper surface. When this happens, the
operator can feel a sudden resistance to further turning. At this
point, the container cap 1 has been turned on to the mouth of the
cushioned cup 2, a tight lock has taken place between the cap and
cup and no liquid will leak out between the cap and the cup.
The top view shown in FIG. 2 shows the knurled circumferential
connecting ring 18 around the periphery of the cover 1. This view
shows the central panel 21 which is part of the central section
which connects to the circumferential connecting ring 18. Four
wings 22 are shown extending from the central panel 21 to the
circumferential connecting wall 18. These wings 22 function to hold
the central panel 21 in place as well as a slight stiffening effect
to the central section. The indents 23 are shown here to be four in
number. They and the wings 22 may be any number depending upon the
size and general configuration of the cup lid. The lid for a normal
size cup such as is carried in the hand operates quite efficiently
with four wings and four indents. For larger cups, more indents and
wings may be used.
The knurled ring 18 helps to give lateral rigidity to the lid as
well as give a surface that the operator may grip when turning the
lid 1 into the cup 2.
The indent bracing panels 13 give lateral support to the inner wall
10 of the channel 5 because they are flat and each bracing panel
lies inwardly of and supports each curved triangular panel 10.
Further, the indents 23 including the channel walls give
considerable tortional stability to the screw-in lid.
Although the discussion above stresses the use of this lid as a
screw-in lid, the lid may also be used effectively as a snap-in lid
by forcing the lid directly down onto a cup. The lid threads will
seat into the soft cushioned material of the cup side wall and a
tight fit is obtained.
The advantages of this invention are that the container cap threads
into the inside of the cup which is made of soft cushioned
material. The primary force applied to the container cap is
compressive rather than tensile. A tight fitting container cap is
made and the cap is not subject to splitting or pop-off as is the
situation with detent means located on the outer wall of the
downwardly opening circumferential channel. A cup need not be
forced with a cup lid since there is no snap-on lid. Close
tolerances need not be maintained in forming the cup of soft
cushioned material since the lid fits a wide range of cups within a
manufacturing size.
While the preferred embodiment has been shown and described, it is
understood that the foregoing is a description of illustrative
embodiment of the invention and it is applicant's intention in the
append claims to cover all forms which fall within the scope of the
invention.
* * * * *