U.S. patent number 3,756,444 [Application Number 05/246,968] was granted by the patent office on 1973-09-04 for tamperproof closure.
This patent grant is currently assigned to Mack-Wayne Plastics Company. Invention is credited to James A. McIntosh.
United States Patent |
3,756,444 |
McIntosh |
September 4, 1973 |
TAMPERPROOF CLOSURE
Abstract
A tamperproof closure adapted to be fitted on a container by a
rotary motion of the closure, for example by means of threads,
includes an inner cap having internal means for engaging the
container, and an outer cap surrounding the inner cap. The outer
cap has an aperture aligned with a projection extending from the
end wall of the inner cap, so that the end walls of the caps are
normally separated, but may be pushed together by forcing the
projection through the aperture. When the caps are forced together
suitable engaging means on the caps permit the caps to be rotated
together. The projection is shaped to inhibit its withdrawal from
the aperture once the caps have been forced together.
Inventors: |
McIntosh; James A. (Upper
Montclair, NJ) |
Assignee: |
Mack-Wayne Plastics Company
(Wayne, NJ)
|
Family
ID: |
22932964 |
Appl.
No.: |
05/246,968 |
Filed: |
April 24, 1972 |
Current U.S.
Class: |
215/220 |
Current CPC
Class: |
B65D
50/041 (20130101) |
Current International
Class: |
B65D
50/00 (20060101); B65D 50/04 (20060101); B65d
055/02 () |
Field of
Search: |
;215/9,46R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hall; George T.
Claims
What is claimed is:
1. In a safety closure for a container of the type having a
cylindrical neck over which a closure is adapted to fit and be
held, the closure being of the type having an inner cap which is
securable over the neck of the container by a rotary motion, and an
outer cap surrounding the inner cap for selectively inhibiting
rotation of the inner cap, and wherein engaging means are provided
on the inner cap and outer cap for mutual engagement in a first
relative axial position of the inner and outer caps, and be
separated at a second relative axial position of the inner and
outer caps; the improvement wherein said inner cap comprises a top
wall and a cylindrical skirt extending downwardly therefrom for
engagement with a container, and said outer cap has a top wall
aligned with the top wall of said inner cap and having a
cylindrical skirt extending therefrom and surrounding the
cylindrical skirt of the inner cap, said inner cap further having a
central projection extending from the top wall thereof toward the
top wall of said outer cap, said outer cap further having an
axially extending aperture aligned with said projection, said
projection having a base adjacent the top wall of said inner cap
that is no greater than the diameter of said aperture, said
projection further having a diameter at its end away from said top
wall of said inner cap that is greater than the diameter of said
aperture, whereby said projection holds said outer cap spaced from
said inner cap in said second position and said projection may be
forced through said aperture to attain said first position.
2. A tamperproof closure for a container of the type having a
threaded neck, said closure comprising an inner cap having a first
top wall and an internally threaded first cylindrical skirt
extending therefrom for engaging the threaded neck of the
container, said closure further comprising an outer cap having a
second top wall and a second cylindrical skirt extending therefrom,
said second skirt being positioned to surround said first skirt, a
central projection extending from said first top wall toward said
second top wall, a central aperture in said second top wall aligned
with said projection, said projection having a base portion
adjacent said first top wall of smaller cross sectional dimension
than said aperture and an end portion of greater cross sectional
dimension than said aperture, whereby said projection holds said
second top wall in a first position spaced from said second top
wall and said second top wall may be forced toward said first top
wall with said projection extending through said aperture to a
second position, and engaging means on said inner and outer caps
positioned to permit free relative rotation of said inner and outer
caps in said first position and to transmit rotary movement from
said outer cap to said inner cap in said second position.
3. The tamperproof closure of claim 2 wherein said projection has a
circular cross section and said aperture is round.
4. The tamperproof closure of claim 2 further comprising mutually
engaging means on said inner and outer caps inhibiting separation
of said inner and outer caps beyond said first position.
5. The tamperproof closure of claim 4 wherein said mutually
engaging means comprises an annular inwardly extending bead at the
bottom of said second cylindrical skirt for engaging the bottom of
said first cylindrical skirt.
6. The tamperproof closure of claim 2 wherein said engaging means
comprises axially extending ribs on the outer circumference of said
first cylindrical skirt, and axially extending ribs on the inner
surface of said second cylindrical skirt.
7. The tamperproof closure of claim 6 wherein the ribs on said
first cylindrical skirt extend outwardly from the bottom edge of
said first cylindrical skirt, and the ribs on said second
cylindrical skirt extend downwardly from said second top wall.
8. The tamperproof closure of claim 2 wherein said engaging means
comprises radially extending ribs on the top of said first top wall
and radially extending ribs on the bottom of said second top
wall.
9. The tamperproof closure of claim 2 wherein said engaging means
comprises projection means extending from said second top wall
toward said first top wall, and recess means in said first top wall
alignable with said projections in said second top wall.
10. The tamperproof closure of claim 2 wherein said second top wall
further includes a recess surrounding said aperture on the side
thereof toward said first wall, whereby said projection engages
said recess in said first position.
Description
This invention relates to closures for containers, such as bottles
or the like, in which the closure is adapted to engage and be held
on the container as a result of a relative rotary motion between
the closure and the container. Conventionally, of course, such caps
employ suitable threads for engaging threads on the container. The
invention is specifically directed to the provision of a cap of
this type which also includes an outer member surrounding the inner
cap for inhibiting rotation of the inner cap, but being capable of
manipulation to a position of mutual engagement so that the inner
cap may be rotated by rotation of the outer member.
Closures of the above type have been employed in the past, and an
example of such a closure is disclosed in my U.S. Pat. No.
3,520,435, which issued on July 14, 1970. As noted in the
disclosure of my aforementioned patent, there are many products in
daily use in modern households which may be harmful or dangerous
when taken internally, so that conventional screw-on type of caps
present a hazard in households where small children have access to
the containers. It is of course no solution to this problem to
advise people to place the containers in inaccessible locations. As
a consequence, numerous forms of tamperproof closures have been
suggested, as exemplified by my above mentioned patent.
Another problem also exists with respect to the provision of
closures for containers, whether they be tamperproof or not.
Containers of various materials, both harmful and nonharmful, and
including some foodstuffs, are frequently openly displayed on the
shelves of stores. Unfortunately, in view of the ready
accessibility of these containers, it has been noted on some
occasions that employees of the premises as well as customers
occasionally open the containers for the purpose of sampling or
use, and then return the partially emptied containers to the
shelves. Subsequent purchasers of the partially emptied containers
are frequently unaware of the tampering with the container they
have purchased, and do not obtain the full value for their money.
The possibility also arises that prior opening of the containers
may result in the spoiling of the product.
In order to overcome this problem, it is further desirable to
provide a closure which will provide a good indication to a
purchaser of whether or not it has been tampered with. This problem
can of course be overcome by the use of various seals, but many
such tamperproof arrangements unnecessarily increase the expense in
producing the closure member.
It is therefore the object of this invention to provide an
inexpensive and easily manufactured tamperproof closure for a
container, in which the operation of the closure by, for example,
children, will be difficult, and in which the fact that the closure
has been tampered with is normally readily visible.
Briefly stated, in accordance with my invention, I provide a
tamperproof closure comprised of an inner cap and an outer cap. The
inner cap has a top wall with a cylindrical skirt extending
therefrom, the internal surface of the inner cap having a
configuration, such as threads, permitting the inner cap to be
firmly held on the neck surrounding an opening in a container. The
outer cap also has a top wall and a cylindrical skirt extending
therefrom. The outer cap is positioned so that its cylindrical
skirt radially surrounds the cylindrical skirt of the inner cap,
and means are provided for permitting limited relative axial
movement between the inner and outer caps, while inhibiting total
separation of the caps. In the preferred embodiment of the
invention, the inhibiting means is in the form of an annular bead
extending inwardly from the bottom of the cylindrical skirt of the
outer cap, to engage the bottom of the cylindrical skirt of the
inner cap.
A projection is provided on the top wall of the inner cap and
extending toward the outer cap, and an aperture is provided in the
top wall of the outer cap aligned with the projection. The
projection preferably has a round cross section, with its top of
greater diameter than the diameter of the aperture, and its base
diameter less than or equal to the diameter of the aperture. The
projection thereby holds the two caps spaced apart, but the caps
may be forced together so that the projection extends through the
aperture. The inner and outer caps are provided with mutually
engagable means, such as lugs, which are out of engagement to
permit free rotation of the outer cap with respect to the inner cap
when the top walls thereof are spaced apart by the projection, but
which engage when the outer cap is forced downwardly onto the lower
cap so that the projection extends through the aperture, thereby
permitting rotation of the inner cap by manual rotation of the
outer cap.
By providing an outer cap that is normally freely rotatable with
respect to the inner cap, the closure device according to my
invention inhibits opening of the closure device by persons not
aware of the necessity for urging the projection through the
aperture, such as small children. In addition, when the projection
extends through the aperture, it is clearly evident that the
closure has been tampered with. The projection is shaped so that
its withdrawal from the aperture is inhibited once the caps have
been forced together.
The invention will now be described in greater detail with
reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of a closure device according to the
invention in place on the neck of a container;
FIG. 2 is a cross sectional view of a closure device according to a
preferred embodiment of my invention, with the top walls of the
inner and outer caps being separated by the projection to inhibit
rotation of the inner cap, the cross section being parallel to the
axis of the device;
FIG. 3 is a cross sectional view of a preferred embodiment of a
closure according to the invention, differing from the view of FIG.
2 in that the projection in the top wall of the inner cap has been
forced through the aperture in the top wall of the outer cap to
permit rotation of the inner cap;
FIG. 4 is a cross sectional view taken along the lines 4--4 of FIG.
3, and illustrating the engagement between the engaging means of
the inner and outer caps;
FIG. 5 is a cross sectional view of a portion of a modification of
the closure of FIGS. 2 and 3;
FIG. 6 is a cross sectional view of a portion of another
modification of the closure of FIGS. 2 and 3;
FIG. 7 is a cross sectional view of a portion of still another
modification of the closure of FIGS. 2 and 3;
FIG. 8 is a cross sectional view of a further modification of a
portion of the closure of FIGS. 2 and 3; and
FIG. 9 is a cross sectional view of a still further modification of
a portion of the closure of FIGS. 2 and 3.
Referring now to the drawings, and more in particular to FIG. 1,
therein is illustrated a closure device 10, according to the
invention, in position on the neck of a typical container 11. As is
apparent in FIG. 1, the only portions of the clsoure that are
normally visible are an outer cap 12 having a top wall 13 with a
central aperture 14, and a cylindrical skirt 15 extending
downwardly from the top wall 13 around the neck of the container.
The bottom of the aperture 14 is closed by the top 16 of a
projection, which will described in more detail in the following
paragraphs.
Referring now to FIG. 2, the closure according to the invention
further comprises an inner cap 20 disposed within the outer cap 12,
and coaxial therewith. The inner cap has a top wall 21 aligned with
the top wall 13 of the outer cap, and a cylindrical skirt 22
extending from the top wall 21 and radially surrounded by the
cylindrical skirt 15 of the outer cap. The inner cap 20 is provided
with a configuration, such as threads 23 on the inside of the
cylindrical skirt 22, to permit affixing of the inner cap to
suitable configurations, such as threads, on the neck of the
container 11 of FIG. 1. It will be understood, of course, that the
form of the configuration for holding the inner cap onto the
container does not form a part of the invention, and any
configuration permitting the inner cap to be held on the container
by virtue of at least a rotary movement is contemplated, since as
will be apparent in the following paragraphs the closure is adapted
to inhibit undesired rotary movement of the inner cap.
A centrally positioned projection 25 is provided on the top of the
top wall 21 of the inner cap, and extending toward the top wall of
the outer cap. The projection 25 preferably has a round cross
section. The base 26 of the projection 25 has a diameter which is
equal to or slightly less than the diameter of the aperture 14,
while the top 16 of the projection 25 has a diameter greater than
the diameter of the aperture 14. The projection 25 and aperture 14
are centrally disposed, i.e. along the axis of the closure, so that
their alignment will be maintained with relative rotation of the
outer and inner caps. For example, the projection may have an
annular knob-like protrusion 27 at its uppermost portion. The
projection 25 is intended to hold the top walls of the inner and
outer caps in spaced apart positions as shown in FIG. 2, and if
desired an annular recess 28 may be provided in the bottom of the
aperture 14, against which the end 16 of the projection rests when
the caps are in the spaced apart position.
It is of course desirable that the inner and outer caps be
relatively unseparable while permitting a limited axial movement
therebetween. For this purpose, an annular inwardly extending bead
30 is provided at the bottom of the cylindrical skirt 15 of the
outer cap, the bead being positioned to engage the bottom of the
cylindrical skirt 22 of the inner cap when the top walls of the
caps are in their spaced apart position as illustrated in FIG. 3.
The bead 30 thereby prevents the top walls of the caps from moving
further apart, but permits their movement to a closer together
position. The provision of the annular bead 30 is exemplary only,
since such a configuration is easy to form in plastic members, and
it will be understood that any conventional interengagement between
the inner and outer caps which serves the above described function
are contemplated herein.
While the top of the projection 16 is of larger diameter than the
aperture 14, in accordance with the invention the outer cap 12 is
made of a material which is sufficiently flexible and deformable to
permit the projection 25 to be forced through the aperture 14 upon
the application of pressure to the upper cap. For example, it is
preferred that the outer cap be molded of a conventional plastic
material, especially since such materials are readily formed to the
other configurations of the cap. The requirements for materials of
the inner cap are not as demanding with respect to resilience,
although the inner cap is preferably molded from a similar
material. Thus, the materials employed for the inner cap and the
outer cap may be made in accordance with the closure member
disclosed in my above mentioned U.S. Pat. No. 3,520,435.
FIG. 3 illustrates the closure of FIG. 2 in which the outer cap has
been forced downwardly so that the projection 25 extends
therethrough. In this figure it is seen that the enlarged end 16 of
the projection extends beyond the aperture 14, to inhibit movement
of the outer cap back to its spaced apart position as illustrated
in FIG. 2. The relative dimensions of the end 16 of the projection
25 and the aperture 14 are dependent upon the flexibility and
deformability of the materials employed, and these dimensions
should thus be selected so that the downward movement of the outer
cap is accomplished only with some degree of difficulty. The recess
28 has been provided in order to permit a degree of freedom in the
selection in the thickness of the top wall of the outer cap from
the standpoints of strength and necessary flexibility, while still
permitting a reduction in the overall longitudinal dimension of the
closure. As illustrated in FIG. 3, when the outer cap has been
forced down to the inner cap, the annular bead 30 is moved to a
position spaced from the bottom of the skirt 22 of the inner
cap.
The closure according to the invention is arranged so that the
outer cap 12 is freely rotatable with respect to the inner cap 20
when the top walls of the two caps are held apart by the projection
25 in the position illustrated in FIG. 2, but that the inner cap
and outer cap are rotatable together when the outer cap has been
moved to the position illustrated in FIG. 3. For this purpose,
according to one embodiment of the invention, as illustrated in
FIGS. 2 and 3, inwardly extending ribs 35 are provided inside the
cylindrical skirt 15 of the outer cap, and outwardly extending ribs
36 are provided on the outer surface of the cylindrical skirt 22 of
the inner cap. A plurality of such ribs 35 and 36 may be provided
around the circumference of the cylindrical skirts as illustrated
in FIG. 4. The ribs 35 and 36 are positioned on their respective
cylindrical skirts so that they are axially separated when the
inner and outer caps are held apart as illustrated in FIG. 2, but
are mutually engagable when the inner and outer caps are moved
together as illustrated in FIG. 3. In the embodiment of my
invention illustrated in FIGS. 2 and 3, the ribs 36 are adjacent
the bottom of the skirt 22 of the inner cap, extending upwardly
from an outwardly extending annular bead 37 at the bottom of the
cylindrical skirt 22. The bottom of the cylindrical skirt 15 has a
diameter, as illustrated at 38, to permit clearance of the ribs 36,
while the upper portion 39 of the outer cap has a slightly reduced
diameter to permit clearance with the upper portion of the
cylindrical skirt of the inner cap. The ribs 35 are provided in the
central region of the cylindrical skirt 15 between the portions 38
and 39 thereof. The ribs 35 and 36 are preferably relatively narrow
in the circumferential direction, and are spaced apart, so that
they do not inhibit movement of the outer cap to the position
illustrated in FIG. 3. As an example, it has been found that from 5
to 10 such ribs in each cap are adequate.
In the assembly of the closure according to my invention, it is
preferred that the inner cap first be placed on the neck of the
container and rotated to seal the neck of the container. Since the
outer cap is of a flexible material, the outer cap may then be
placed over the top of the inner cap, and the flexibility of the
member will permit the walls of the outer cap to be flexed
outwardly as the outer cap is forced downwardly until a position at
which the annular bead 30 just snaps over the bottom of the
cylindrical skirt 22. The outer cap should not be forced downwardly
further than this, so that the projection 25 is never forced
through the aperture 14 until the contents of the container are
ready for use.
The closure of the invention may of course include sealing means,
such as sealing rings integrally molded in the inner cap, if
desired.
As illustrated in FIG. 3, inspection of a container incorporating a
tamperproof cap according to the invention will readily reveal that
the closure has been tampered with, since in this case the
projection 25 will extend through the aperture 14 and be readily
visible at the top of the closure.
In order to provide tamperproof characteristics in the arrangement
according to the invention, it is preferred that the components of
the tamperproof cap be shaped to inhibit the removal of the
projection 25 from the aperture once the outer cap has been forced
downwardly. Thus, the top of the aperture 14 is as small as
possible with respect to the diameter of the projection to provide
a close fit, and the underside of the enlarged end 16 of the
projection is formed as flat as possible, as determined by the
molding techniques employed in the fabrication of the member, so
that withdrawal of the projection from the aperture is as difficult
as possible. In addition, withdrawal of the projection from the
aperture is inhibited by the fact that when the outer cap is forced
downwardly, the bottom of the outer cap is at its closest position
to the container 11, so that it is difficult to get enough purchase
on the bottom of the outer cap with the fingers to apply sufficient
force on the outer cap to effect the removal of the projection from
the aperture. Movement of the outer cap in the downward direction,
however, is facilitated, for example, by providing a chamfer in the
lower portion of the aperture, such as the annular recess 28, and
by forming the top of the enlarged end 16 with as close to a full
round surface as possible, at least in the portion thereof which
engages the aperture. In addition, it is much easier to force the
outer cap downwardly since there is ample surface on the top of the
outer cap surrounding the aperture to enable the user to apply the
necessary force thereto.
While as above stated it is preferred that the projection 25, and
hence the aperture 14, have round cross sections, it is also
contemplated that irregular cross sections may be permitted for the
projection and aperture so that the irregular surfaces thereof can
engage upon movement of the outer cap to the position illustrated
in FIG. 3, and thereby permit rotation of the inner cap by virtue
of the engagement of the aperture 14 and the projection 25. In such
case the lugs or other similar engaging means may of course be
dispensed with if desired, and the diameters of the projection 25
and hence the aperture 14 should be increased to permit the
application of the necessary rotary force to the inner cap.
Referring now to FIG. 5, therein is illustrated a modification of
the closure of FIGS. 3 and 4 with respect to the ribs provided for
mutual rotation of the inner and outer caps. In this arrangement,
the inner cap is provided with spaced apart longitudinally
extending ribs 40 of the same general form as illustrated in FIGS.
3 and 4, but extending upwardly toward the top wall of the inner
cap for a greater distance, but not completely to the top of the
inner cap. The outer cap as illustrated in FIG. 5 is of
substantially equal diameter throughout its length, and internal
ribs 41 are provided extending from the top wall 13 downwardly pass
the top of the top wall of the inner cap but not so far as the ribs
40. When the inner and outer caps are spaced apart in the position
illustrated in FIG. 5, the ribs 40 and 41 are axially separated, so
that the outer cap can rotate freely, but the lower edges of the
ribs 41 engage the upper edges of the ribs 40 when the outer cap is
moved to its lowermost position, to permit mutual rotation of the
inner and outer caps.
In the embodiment of the invention illustrated in FIG. 6, the ribs
43 on the outside of the inner cap extend throughout the length of
the inner cap, while the longitudinal ribs 44 on the inside surface
of the cylindrical skirt of the outer cap do not extend downwardly
as far as the top of the inner cap when the inner and outer caps
are in their separated position as illustrated in FIG. 6. When the
outer cap is moved downwardly, the ribs 44 engage the ribs 43 to
permit mutual rotation of the inner and outer caps.
In the further embodiment of FIG. 7, instead of providing ribs on
the inner cap, the top of the inner cap may be provided with short
longitudinally extending recesses 45, while the inside surface of
the outer cap is provided with longitudinally extending ribs 46
adapted to engage the recesses 45 when the outer cap is moved
downwardly (not shown), but be separated when the outer cap is held
to its uppermost position by the projection 25.
In still another embodiment of the invention, as illustrated in
FIG. 8, instead of providing the ribs as in the above examples of
the invention, the bottom of the top wall 13 of the outer cap may
be provided with downwardly extending projections 48 adapted to
engage suitable recesses 49 in the top of the top wall of the inner
cap when the outer cap is moved downwardly, but be separated
therefrom when the outer cap is in its uppermost position as
illustrated. The projections 48 and recesses 49 may have circular
cross section, in which case their mutual alignment is required
before fully moving the outer cap toward the inner cap.
Alternatively, of course, the recesses may have triangular cross
sections, with radially extending apices, the recesses being
provided in a continuous configuration about the circumference of
the top wall, with the projections 48 having a similar cross
section, to obviate the necessity for close alignment of the inner
and outer caps before moving the outer cap downwardly toward the
inner cap.
In a still further embodiment of the invention, the inside surface
of the outer cap may be provided with ribs 55 extending radially
inwardly on the bottom of the top wall 13 from the cylindrical
skirt, the top circumference of the top wall 21 being provided with
radially inwardly extending ribs or recesses 56, so that the ribs
or recesses 56 and the ribs 55 are mutually separated when the
outer cap is held spaced apart from the inner cap by the projection
25, as illustrated, but mutually engaged for common rotation of the
inner and outer caps when the outer cap is moved downwardly toward
the inner cap.
While the invention has been disclosed with reference to a limited
number of embodiments, it will be obvious that many variations and
modifications may be made therein without departing from the spirit
and scope of the invention, and it is therefore intended that the
invention as recited in the following claims cover all such
variations and modifications as may be obvious from the above
disclosure.
* * * * *