Note: Descriptions are shown in the official language in which they were submitted.
~~'~" 93/07071 2 1 2 0 7 1 3 PCI/US92/07286
CHILD-RESISTANT PACKAGE HAVING
PRELOADED LOCKING MECHANISM
TECHNICAL FIElD
The present invention has relation to an improved Dackage
for storing and dispensing materials which can be harmful,
particularly if improperly ingested. Such materials may be in solid.
tablet, granular, powdered, semi-solid, paste or liquid form.
In a particularly preferred embodiment, the present
invention has relation to a package for storing and dispensing
medicaments, such as analgesic tablets or the like.
The present invention has further relation to such a
-~ package which is resistant to opening by the majority of children
coming in contact with it, yet which can be opened without undue
difficulty by adults whose manual dexterity may, at least to a
degree, be impaired.
- The present invention has further relation to such a
-~ package which can be inexpensively manufactured to facilitate
disposal thereof once the contents have been completely disDensed
from the package. The present invention has still further relatlon
to methods for manufacturing such a package.
BACKGROUND ART
-3 Child resistant packaging is known for being both a
blessing and a curse. It is a great concept for preventing children
from opening potentially dangerous materials such as medications. ~ut
for adults, especially the elderly, such packaging can be a nuisance.
Because of deteriorating health, the elderly tend to rely
-5 on medication more than the average person. However, simply making
medication more easily accessible to the elderly bears with it the
risk that the contents of the package could be accessible to children
who could be seriously injured if they obtain access to the contents
of a medicament package and ingest the medicaments contained therein.
The aforementioned problems are recognized generally in the
packaging industry, particularly the pharmaceutical industry.
_ wog3~b70~ 3 ~ PCr/US92/07286
Numerous articles have been written on the subject. See for example
~The Oual Vial" published in the Fall 1988 edition of ~Qy~ magazine.
One package which has met with good success in providing
child resistance without imposing undue opening difficulty for adults
5 whose manual dexterity may, at least to a degree, be impaired is
disclosed in commonly assigned U.S. Patent 4,948,002 issued to
Thornock et al. on August 14, 1990. While packages~
of the type disclosed in the
aforementioned commonly assigned Thornock et al. patent have faired
extremely well in test protocols involving both children and adults
having impaired manual dexterity. it has quite unexpectedly been
discovered that child resistance of the package can be enhanced even
further without making the package more difficult to open by adults
if the spring-like pushtabs containing vertical extensions ~hich
engage interlocking teeth on the innermost surface of the closure
skirt are configured so that application of the closure to the
package will require a degree of deformation of the spring-like
pushtabs whenever the closure is applied to the package in a fully
assembled, interlocked condition. This is normally accomplished by
~~ configuring the spring-like pushtabs so that their uppermost ends
project outwardly to a degree prior to assembly of the closure onto
the package. The practical effect of this configuration is that the
vertical extensions on the spring-like pushtabs are, at least to a
degree, preloaded so as to exert a force against the innenmost
surface of the closure skirt once the closure has been fully
assembled onto the package.
OBJECTS Of THE INVENTION
Accordingly, it is an object of the present invention to
provide a package which exhibits improved child resistance without
significantly increasing the difficulty of opening by adults having
impaired manual dexterity.
It is another object of the present invention to provide
methods for producing such an improved package.
3i
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DISCLOSURE OF THE INVENTION
- In a particularly preferred embodiment, the present
invention comprises a package for dispensing potentially dangerous
materials, such as medicaments, e.g., analgesic tablets or the like.
The package preferably comprises a bottle, a collar which snap fits
onto the uppermost portion of the bottle and a screw-on closure, as
generally disclosed in the aforementioned commonly assigned U.S.
Patent 4,948,002 to Thornock et al. or a child-resistant attachment
of the type generally disclosed in co-pending Canadian Patent Application
2,117,433 filed in the names of Peter W. Hamilton, Robert S. Dirksing
and Reuben E. Oder on January 19, 1993 and entitled ADULT-FRIENDLY
CHILD-RESISTANT ATTACHMENT FOR CONTAINERS USED TO STORE
POTENTIALLY DANGEROUS MATERIALS. Child-resistant attachments
of the type disclosed in co-pending Canadian Patent Appl. 2,117,433
may be formed separately from the bottle or container used to
house the medicament or other potentially hazardous materi~l and
thereafter secured to the container or they may be integrally formed
with the container. Regardless of its exact configuration and how it
is formed, the collar preferably includes a pair of spring-like
pushtabs which include vertical extensions at their uppermost ends.
The closure has a skirt which includes a pair of interlocking teeth,
sometimes referred to as pawls, which resist unscrewing of the
closure once the closure has been completely applied to the bottle
unless the opposed pushtabs on the collar are depressed so as to
disengage their vertical extensions from the interlocking teeth on
the innermost surface of the closure skirt.
In improved packages or attachments of the present
invention, the portion of the collar containing the spring-like
pushtabs to which the vertical extensions are secured is initially
produced so that in their undeformed condition, the vertical
extensions on the spring-like pushtabs are further apart than the
corresponding innermost surfaces of the closure skirt when the
closure is fully applied to the package or the attachment. As a
result, application of the closure to the package causes at least a
degree of resilient deformation of the spring-like pushtabs and/or
the vertical extensions attached thereto so that the vertical
~c,
'''O 93/07071 2 1 2 0 7 1 3 PCI'/US92/07286
4 __
extensions are preloaded against the innermost surface of the closure
skirt when the package or attachment is in its child resistant
condition.
It is believed that preloading of the vertical extensions
of the spring-like pushtabs against the innermost surfaces of the
closure skirt insures positive locking with the interlocking teeth on
the interior of the closure skirt even in situations where
manufacturing tolerances drift beyond specified limits, i.e., the
vertical extensions of the spring-like pushtabs must always undergo
enough inward movement to clear the interlocking teeth on the
interior of the closure skirt in order to permit unscrewing of the
closure. If no preloading of the spring-like pushtabs is present,
drifts in manufacturing tolerance can reduce the required amount of
travel for the vertical extensions of the pushtabs and thereby permit
unscrewing of the closure with less depression of the spring-like
pushtabs.
It is further believed that adults having impaired manual
dexterity do not find the preloading force exerted by the vertical
extensions on the spring-like pushtabs against the innermost surfaces
of the closure skirt to pose any additional opening difficulty for
them because the level of preloading is not so great as to
significantly increase the total force required to release the
interlocks and permit unscrewing of the closure.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly
pointing out and distinctly claiming the present invention, it is
believed the present invention will be better understood from the
following description in conjunction with the accompanying drawings
in which:
Figure l is an exploded simplified perspective view of a
particularly preferred package of the present invention;
Figure 2 is a simplified cross-sectional view of the
package generally shown in Figure 1 after the package has been
assembled, said view being taken at a point which is perpendicular to
anti-rotation lugs 28 on bottle 12;
SUBSTITUTE SHEET
:~0 93'/07071 ~ ~ 2 ~ 7 ~ ~ PC~r/US92/07286
Figure 3 is a simplified cross-section generally similar to
that of Figure 2, but showing a cross-section through anti-rotation
lugs 28 on bottle 12;
figure 4 is a simplified cross-sectional view of the
package of figure 2 taken through section line IV-IY of Figure 2;
Figure 5 is a simplified partial perspeotiYe view of the
package of Figure 1 illustrating the position of the vertical
extensions on the spring-like pushtabs prior to application of the
closure to the package;
figure 6 is a side elevation view of a particularly
preferred child resistant attachment of the present invention;
Figure 7 is a cross-sectional view of the attachment shown
in figure 1, said view being taken along section line I-I of Figure
6;
lS Figure 7A is a cross-sectional view of the child resistant
attachment of Figure 6 taken along section line II-II of Figure 6;
Figure 8 is a cross-sectional view of the attachment shown
in Figure 6 with the pushtabs in the depressed condition, said view
being taken at a point corresponding to section line I-I of Figure 6;
Figure 8A is a cross-sectional view of the child resistant
attachment of Figure 6 with the pushtabs in the depressed condition.
said view being taken at a point corresponding to section line II-II
of Figure 6;
Figure 9 is a side elevation view of a child resistant
~5 attachment of the present invention wherein the finish portion is
integra11y molded to a vial; and
Figure 9A is a cross-sectional view of the chi1d resistant
att~r~ t and vial of Fi~ure 9.
DETAILED DE5CR~PtION OF TH~ INVENTION
Figure 1 shows an exploded view of an improved child
resistant package 100 of the present invention. The basic package
100 is of the type generally disclosed in com~only assigned U.S.
Patent 4,9~8,002 issued to Thornock et al. on August 14, 1990.
However, the present disclosure in the context of Thornock et
al. type package is intended to be a non-limiting illustrative
example. Package 100 is particularly well
-vo 93/07071 2 1 2 0 ~ ~ 3 PCI/US92/07286
suited for housing medicaments. Package 100 is particularly well
suited for housing medicaments, such as analgesic tablets 20.
However, advantageous use of packages of the present invention is in
no way limited to the field of medicaments or even to tablets.
Packages of the present invention may be used for storing and
dispensing nearly any potentially dangerous material whether in
solid, tablet, granular, powdered, semi-solid, paste or liquid form.
The accompanying description in the context of a medicament tablet
package is merely to facilitate a complete understanding of
particularly preferred embodiments of the present invention.
Figure 1 shows a bottle 12, which is preferably made of
polyethylene, the most common and inexpensive analgesic bottle
material. The bottle 12 is preferably injection blow molded with a
wall thickness in the range of about 0.015 inches to about 0.050
inches. The particular bottle 12 shown in Figure 1 has a base 14
with a substantially constant elliptical cross-section. In a
particularly preferred embodiment the ratio of ellipse minor
dimension to major dimension is approximately 0.7.
The upper shoulder portion 16 of the bottle 12 is
preferably an elliptical cone in shape. The cone included angles of
upper shoulder portion 16 preferably range between cDout 36- and
about 70-, as measured about the periphery of the bottle 12. In a
particularly preferred exemplary embodiment, th~ basa 14 exhibits a
major axis of about 1.75 inches, a minor axis of about 1.25 inches
and an overall height of about ~.12 inch~s. The altitude of the
truncated cone of shoulder portio~ 16 is about 0.75 inches in this
exemplary embodiment.
Above the should4r portion 16 of bottle 12 is a cylindrical
finish portion 18, wh~ch is, in the aforementioned exemplary
: ~- t, about 0.5 inches in height. The three portions, base
portion 14, shoulder portion 16, and finish portion 18 of bottle 12
are preferably concentrically aligned on a common vertical axis.
The internal diameter of finish 18 is a function of the
diameter (or other major dimension if non-round) of tablet 20 and the
fill rate of tablets. In particular, the inside diameter of finish
18 should be sufficiently large that bridging of tablets 20, entering
the finish 18 from a tapered filling chute, is minimized. Once the
2 1 2 0 7 ~ 3 PCI'/US92/07286
inside diameter of finish 18 has been selected, the diameter of the
uppermost end of the truncated cone comprising shoulder portion 16 is
determined, i.e., it is substantially equal the inside diameter of
finish 18. The included cone angles selected for shoulder portion 16
then determine the major and minor axis dimensions of base portion
14. For analgesic tablets 20 having a diameter of about 0.3~5
inches, the major axis dimension of base portion 14 typically is in
the range of about 1.5 inches to about 2.5 inches. ~he height of
base portion 14 is selected to provide whatever overflow volume is
desired in the package 100.
While any suitable means, e.g., a combination of lugs and
screw threads, can be employed to rotatably and releasably secure
closure 52 to the finish portion 18 of bottle 12, complementary
threads are particularly preferred.
The threads 22 on finish 18 are preferably double lead
threads, each with a lead angle which provides a thread pitch of
about 0.1 inches to about 0.13 inches per half revolution.
~ ndented recess 24 located at the base of shoulder portion
16 of bottle 12 and outwardly projecting ring 26 located at the
uppermost end of shoulder portion 16 of bottle 12 are intended to
provide snap-fit attachment of collar 32, also shown in Figure 1. As
will be described in greater detail in the following paragraphs,
anti-rotation lugs 28 extending from shoulder portion 16 of bottle
12, just below outwardly projecting ring 26, are intended to
interlock with collar 32 in order to prevent rotation of collar 32
relative to bottle 12 when removal torque is applied to the closure
52.
Collar 32 is preferably an injection molded part having an
ou~s;~ shape of a truncated cone intersecting an elliptical cylinder
of the same shape as base 14 of bottle 12. Collar 32 is preferably
made of a polymer which has an adequate bending modulus to provide a
pair of resiliently deformable spring-like pushtabs 34. In the
embodiment shown in Figure 1, spring-like pushtabs 34 are molded so
that they are cantilevered at their base in their at rest position in
the opposing conical sides of collar 32. Preferably they have a
thickness substantially equal to that of the walls of collar 32,
e.g., between about 0.040 inches and about 0.060 inches.
W O 93/0707l 2 1 2 ~ 7 1 ~ PC~r/US92/07286
The top of each spring-like pushtab 34 has a vertical
extension 36 which projects above the top edge of collar 32. ~he
pushtab vertical extensions 36 interlock with teeth 62 on the
innermost surface of the outer skirt 60 of closure 52 when the
closure 52 is fully threaded onto the finish portion 18 of bottle 12.
As can be most clearly seen from the perspective view of
Figure 5 and the cross-section of Figure 4, the spring-like pushtabs
34 are preferably molded so that in their undeformed condition their
vertical extensions 36 which project above the top edge of collar 32
exhibit a dimension Xl, as measured across their outermost surfaces,
which is slightly greater than the corresponding internal dimension
X2, which corresponds to the points of contact between the vertical
extensions 36 and the opposing innermost surfaces of the closure
skirt 60 immediately adjacent the closure teeth 62 when the closure
52 is fully assembled onto the package. As a result of dimension Xl
being slightly larger than dimension X2, application of the closùre
to the package causes a degree of deformation of the spring-like
pushtabs 34 and/or the vertical extensions 36 attached thereto once
the teeth 62 on closure skirt 60 pass by, thereby preloading the
outermost surfaces of the vertical extensions 36 against the
corresponding innermost surfaces of skirt 60 whenever the closure is
in its fully engaged position. This is represented by the outwardly
directed forces F1, as shown in the cross-section of Figure 4.
While the difference in dimensions Xl and X2 may be
relatively small, e.g., on the order of about 0.001 inches and about
0.050 inches, it has unexpectedly been learned that the improved
p~r~ of the present invention employing preloaded spring-like
p~lsht~hs 34 significantly increase the child resistance of the
package without at the same time causing significantly increased
difficulty of opening of the package by adults having impaired manual
dexterity.
For a package which fits within the user's palm, and which
is to be opened by applying the user's thumb and forefinger to the
opposing spring-like members 34 to release the teeth 62 on closure
skirt 60 and thereby permit unscrewing the c10sure 52 from the
package, the amount of preloading force exerted by the vertical
extensions 36 against the corresponding innermost surfaces of the
~'~ 93/07071 2 12 0 7 ~ 3 PCI'/US92/07286
closure skirt 60 need not be extremely high. For example, forces in
~ the range of between about 0.01 pounds and about 2.00 pounds, as
measured by pressing against the uppermost end of one of the opposing
spring-like pushtabs 34, have been found to function reasonably well
in accomplishing the objectives of the present invention. In a
particularly preferred embodiment, a preloading force F1 of about
0.25 pounds, as measured by pressing against the uppermost ends of
the opposing spring-like pushtabs 34, has been found to function
extremely well both in terms of improving child resistance and
avoiding any significant increase in difficulty when the package is
to be opened by adults having at least a degree of impairment to
their manual dexterity.
While the precise phenomenon which produces the foregoing
improved result is not fully understood, it is recognized that
preloading of the spring-like tabs 34 in the foregoing manner will
insure that the vertical extensions 36 must always undergo at least
enough travel to release them from teeth 62 on closure skirt 60.
Specifically, if the outermôst surfaces of vertical extensions 36 are
always maintained in physical contact against the corresponding
innermost surfaces of closure skirt 60, the opposing spring-like
pushtabs 34 must always undergo at least enough movement so that the
vertical extensions 36 will clear the interlocking teeth 62 on the
innermost surface of the closure skirt.
In addition, since children do not typically understand the
mechanism by which opening occurs in a child resistant package, it is
believed that preloading of the spring-like pushtabs 34, which offers
a degree of initial resistance to their depression, naturally tends
to dtscourage children from attempting to simultaneously further
depress the opposing pushtabs while concurrently applying an
unscrewing force to the closure 52. This, in turn, reduces the
chances that the closure will be inadvertently opened by one who does
not understand the opening mechanism.
Perhaps more importantly, because improved packages of the
present invention do not pose increased opening difficulties for
elderly adults or those having a degree of impairment to their manual
dexterity, the adults are more prone to reapply the closure to the
package once the desired amount of contents have been removed rather
WO 93/07071 2 1 2 0 7 1 3 PCI/US92/07286
than leaving the closure only partially secured to or completely off
of the package after the initial opening.
Finally, improved packages of the present invention
employing preloaded spring-like pushtabs 34 enhance the audible
"click" which sounds whenever the teeth 62 on closure member 52 are
advanced past the vertical extensions 36 on spring-like pushtabs 34.
This is due to the fact that the distance between the vertical
extensions 36 on resiliently deformable spring-like pushtabs 34 is
minimized just prior to their clearing teeth 62 on closure skirt 60.
Hence, resiliently deformable spring-like pushtabs 34 are deformed to
their maximum extent just prior to teeth 62 clearing the edges of
vertical extensions 36. This condition combined with the fact that
the vertical extensions 36 would, in the absence of closure member
52, return to their undeformed dimension X1 which is greater than the
corresponding dimension X2 of the interior of the closure skirt,
enhances the audible "click~ which occurs as soon as the vertical
extensions 36 clear teeth 62.
In order to unscrew closure 52 from finish portion 18 once
the closure has been fully assembled onto the finish portion 18 of
bottle 12, both pushtabs 34 must be depressed such that the pushtab
vertical extensions 36 disengage the closure teeth 62 located on the
innermost surface of closure skirt 60. The squeezing force required
to depress pushtabs 34 is preferably great enough to be difficult for
a child, yet low enough that people using the medication, such as
arthritics, can readily depress the opposing pushtabs 34 while
concurrently applying an unscrewing force to the closure 52. The
preferred squeezing force for the pushtabs is believed to be in the
range of about O.S pounds and about S pounds.
In addition, pushtabs 34 are preferably substantially flush
with the outermost surface of collar 32 when closure 52 has been
fully assembled onto the package so that simply grasping the collar
about its entire periphery is unlikely to permit vertical extensions
36 of pushtabs 34 from becoming inadvertently disengaged from closure
teeth 62. Rather, a conscious decision to squeeze the opposing
pushtabs must be made by the user to initiate the opening process.
This minimizes the chance that a child will be able to remove closure
~ 3/07071 2 1 2 0 ~ 1 3 PC~r/US92/07286
52 simply by squeezing the entire periphery of collar 32 in his or
her hand while trying to unscrew closure 52.
To ensure that package 12 will remain functional until all
of its contents have been dispensed, the thickness and length of
spring-like pushtabs 34 should be such that bending stresses
resulting either from the initial preloading or from the deflection
necessary to disengage pushtab vertical extensions 36 from closure
teeth 62 remain below the yield strength of the polymer comprising
collar 32. Materials such as polypropylene have bending modulii and
yield strengths which normally can provide squeeze forces on the
lower end of the aforementioned force range, while materials such as
acrilonitrile-butadiene-styrene (commonly referred to as "ABS~) can
be used to provide squeeze forces on the upper end of the
aforementioned force range.
As can best be seen in Figure 4, the edge 44 of each
pushtab extension 36 interlocks with one of the closure teeth 62 to
prevent the closure 52 from being unscrewed unless both of the
spring-like pushtabs 34 are depressed. These two surfaces contact in
such a way that torque applied in a direction to unscrew closure 52
(direction of arrow 3) will cause pushtab extensions 36 to be pulled
outward against the inner surface of skirt 60 unless the pushtabs 34
have been depressed prior to applying the unscrewing torque. This
feature enhances the child resistance of package 100, since it
prevents high closure removal torque alone from causing pushtab
extensions 36 to become disengaged from closure teeth 62.
As can best be seen in Figures 2 and 3, collar 32 has an
Ln~ardly projecting ring 38 on its lowermost inner surface and an
in~ardly projecting ring 40 on its uppermost inner surface. Inwardly
proiecting ring 40 further includes an inwardly projecting lip 41 on
its lowermost surface. Ring 38 of collar 32 snap-fits into recess 24
of bottle 12 and ring 40 with inwardly projecting lip 41 snaps over
outwardly projecting ring 26 of bottle 12, as generally shown in
Figures 2 and 3. A recess 42 on opposing sides of ring 40 of collar
32 mates with anti-rotation lugs 28 on shoulder portion 16 of bottle
12 to prevent rotation of collar 32 on bottle 12, as discussed
earlier, once the collar has been snapped into place on bottle 12.
W O 93/07071 2 1 2 0 ~ 1 3 PC~r/US92/07286
Closure 52 shown in Figure 1 preferably has an outer skirt
60 which has the same outside diameter as the top of the truncated
cone surface of collar 32. The two teeth 62 projecting from the
inside of skirt 60 are preferably 180- from each other. The teeth 62
preferably have gentle ramps that cam the vertical extensions 36 of
the spring-like pushtabs 34 inward when the closure 52 is being
screwed onto the finish portion 18 of bottle 12, but sharp edges that
interlock with the pushtab vertical extensions 36 once the closure 52
has been fully assembled onto the bottle 12 and is thereafter
twisted in the direction of removal.
Outer skirt 60 of closure 52 preferably has its inner
bottom edge beveled, as shown in Figure 2, to act as a lead-in when
skirt 60 first contacts the top of the vertical extensions 36 of
spring-like pushtabs 34 during closure installation. A second skirt
54 of closure 52, inside of skirt 60, has internal threads 56 which
are complementary to external threads 22 on the finish portion 18 of
bottle 12.
The double skirted closure design permits the use of a
relatively wide, annular, inwardly projecting ring 40 at the top of
collar 32. This relatively wide annular ring 40 provides rigidity to
collar 32 such that it can be readily snap-fit onto bottle 12.
The closure 52 is preferably made of polypropylene for good
frictional properties between the internal closure threads 56 and the
preferred polyethylene exterior threads 22 on finish portion 18 of
bottle 12. Inside closure 52 there is preferably provided a
cardboard or other suitable liner 58, which seals against the top of
the finish portion 18 of bottle 12 when the closure 52 is installed
on the bottle. Because of the variation in thickness and
~ ssibilityof liner 58, the location of teeth 62 relative to the
start of internal closure threads 56 is preferably such that teeth 62
pass beyond the vertical extensions 36 of spring-like pushtabs 34
somewhat when closure 52 is fully assembled onto the bottle. This
minimizes the need for tight tolerances on mating parts.
The relationships of the mating parts of package 100 are
best shown in Figures 2 and 3, which are vertical cross-sectional
views of the bottle 12, collar 32, and closure 52 in their fully
assembled condition. The cross-section of Figure 3 is taken at 90-
~ _ 93~070~ 7 ~ ~ 7 7 ~ i PC~r/US92/07286
to the cross-section of Figure 2 to better show anti-rotation lugs
28.
Figure 4 is a sectional view, taken along section line
~Y-IV of figure 2, which better shows how the teeth 62 on skirt 60 of
closure 52 interlock with the vertical extensions 36 of spring-like
pushtabs 34 once the closure has been fully installed on the bottle.
As will be appreciated by those skilled in the art, the
preloading of the spring-like pushtabs 34 described in connection
with the package embodiment of Figure 1 of the present invention may
also be applied to many of the other package embodiments disclosed in
commonly assigned U.S. ~atent 4,948.002 issued to Thornock et al. on
August 14, 1990.
The particular method by which preloading of the
resiliently deformable spring-like pushtabs 34 will, of course, have
to be adjusted to accommodate the construction of the particular
package. For example, in a particularly preferred embodiment of the
present invention, resiliently deformable spring-like pushtabs 34 are
simply molded so that their uppermost ends project slightly beyond
the outermost surface of shroud 32 prior to application of the
closure 52 to the package. Application of the closure 52 to the
package causes a degree of resilient deformation of the spring-like
pushtabs 34 so that in the assembled condition of the package, the
uppermost ends of spring-like pushtabs 34 are substantially flush
with the outermost surfaces of shroud 32.
For those embodiments of the shroud ~mploying a slmple
hinge-like connection between the spring-like pushtabs and the shrou~
or collar, the auxiliary support members used to impart in-use
spring-l ike resistance to the innermost surface of the pushtabs may
be outwardly extended to a degree so as to produce a slight initial
out~ard orientation of the pushtabs in relation to the surrounding
shroud prior to application of the closure to the package.
The particular method employed to produce a resiliently
deformable spring-like pushtab configuration which will serve to
preload the outermost surfaces of vertical extensions 36 against the
corresponding innermost surfaces of the closure skirt 60 is
non-critical.
~r
7 ~ ~ ~
-- WO 93/07071 PCI/US92/07286
As pointed out earlier in the present specification, the
present invention may also, if desired, be practiced to great
advantage with child-resistant attachments of the type generally
disclosed in co-pending commonly assigned Canadian Patent Application
5 2,1 17,433 filed in the names of Peter W. Hamilton, Robert S. Dirksing
and Reuben E. Oder on January 19, 1993 and entitled ADULT-FRIENDLY
CHILD-RESISTANT ATTACHMENT FOR CONTAINERS USED TO STORE
POTENTIALLY DANGEROUS MATERIALS. Child-resistant attachments
10 of the type disclosed in co-pending Canadian Patent Appl. 2,117,433
may be formed separately from the bottle or container used to house the
medicament or other potentially hazardous material and thereafter
secured to the bottle or container or they may be integrally formed
with the bottle or container.
Figure 6 shows a side view of a preferred child resistant
attachment 2100 of the type generally disclosed in co-pending
commonly assigned Canadian Patent Application 2,117,433, said
attachment further embodying the present invention. Attachment 2100
is particularly well suited for use in conjunction with typical
cylindrical pharmaceutical bottles and vials to dispense
pharmaceutical products, such as tablets. However, the present
invention may also, if desired, be practiced to advantage using
containers having a noncylindrical cross-section, as measured
perpendicular to the container's vertical axis, e.g., elliptical
cross-sections, rectangular cross-sections, etc. Attachment 2100
comprises finish portion 2001 and closure 2002. finish portion 2001
and closure 2002 are preferably injection molded of polypropylene.
polystyrene, polycarbonate, or the like. Finish portion 2001
compri8eR attachment ring 2004 and tab ring or annular collar 2005.
While the annular collar shown in Figure 6 is generally cylindrical
in cross-section, it can, if desired, be of other cross-sectional
shapes, e.g., elliptical, etc., with the cantilevered pushtabs
- (described in detail hereinafter) located at the opposed ends of the
ellipse's major axis. Bead 2003 on attachment ring 2004 is used to
secure attachment 2100 to a pharmaceutical package (not shown). Tab
collar 2005 is interrupted by slots 2006, thereby forming a pair of
opposed cantilevered pushtabs 2007, as shown in Figure 7.
_WO 93/07071 ~ 7 ~ ~ 7 ~ ~ PC}/US9~/07286
Figure 7 is a cross-sectiOnal view of attachment 2100 taken
through section line 1-1 of Figure 6. The closure securement ring 2013
includes first means far rotatably and releasably securing closure
2002 to finish portion 2001. In the ill~strated embodiment, the
; first means comprises helical threads 2009 on the outermost surface
of thread ring 2010. The closure 2002 includes second means
complementary to said first means for rotatably and releasa~1y
securing the closure to the closure securement ring. In the
embodiment of Figure 7, the second means comprises threads 2018 on
the innermost surface of thread col1ar 2017 on closure 2002. ~hile
any suitable re7easab1e securement means, e-g-, a com~ination of luqs
or screw threads. can ~e employed to rotatably and releasably secure
closure 2002 onto finish portion 2001, complementary screw threaas
2009 and 2018, respectively, as shown in Figure 7 are particularly
!5 preferred.
The thréads 2009 on the exterior surface of thread ring
2010 are preferably double lead threads. The pitch of complementary
threads 2009 and 2018 is preferably such that closure 2002 is fully
seated onto finish portion 2001 with approximately 180- of rotation.
The collar 2005~ thread ring 20I0, and attachment ring 2004
are preferably integrally molded and are generally concentric with
one another. The top of each sDring-like pushtab 2007 has a vertical
extension 2008 which proJects above the plane of the top edge of taD
collar Z005. The vertical extensions 2008 interlock with pawls 2015
on the innermost surface of lock ring 2016 of closure 2002 when the
closure 2002 is fully threaded onto finish portion 2001. A channel
2011, formed between the inner surface of tab collar 2005 and thread
rIng 2010, accepts thread collar 2017 when closure 2052 is threaded
onto finish portion 2001.
During assembly of closure 2002 onto finish portion 2001
oawls 2015 must rotate past vertical extensions 200~. ~owever
vertical extensions 2008 interfere with rotation of pawls 2015 and
cause pushtabs 2007 to ~e resiliently deflected inwardly. Gradual
lead-in ramps on pawls 2015 facilitate the deflection. ln general it
is preferred that the lead-in ramos exhibit a qradual inwardly
directed taDer so as to avoid a sudden increase in the reapplicatian
torque required to fully seat the closure 2002 onto the finisn
~'
"0 93/07071 ~ PCI'/US92/07286
16
portion 2001. If desired, the mating surfaces of vertical extenslons
2008 may also be profiled, as generally shown in the croSS-sectiOns
of Figures 7A and 8A, to minimize the reapplication torque required
to fully seat the closure 2002 onto the finish portion 2001 of the
attachment 2100. Both of these features hel 3 to ensure that the user
will properly reapply the closure to restore child resistance to the
package after the package has been opened.
Continued rotation of closure 2002 causes pawls 2015 to
clear the vertical extensions 2008, thereby permitting vertical
extensions 2008 and pushtabs 2007 to resiliently return to the
latched condition shown in Figures 7 and 7A- The finish portion 2001
is mo7ded so that the vertical extensions 2008 exhibit an
unrestrained maximum exterior dimension which is somewnat greater
than the inside diameter of the closure lock ring 2016. In this
1~ situation, application of closure 2002 to finish portion 2001 results
in preloading of the vertical extensions 2008 against the interior
surface of lock ring 2016 when the closure 2002 is fully seated, as
shown in Figure 7A.
The arrangement of threads 2009 and 2018 in conjunction
with vertical extensions 2008 and pawls 2015 is such that latching of
pawls 2015 past vertical extensions 2008 occurs nearly simultaneously
with the seating of closure 2002 onto finish portion 2001, at which
point seal lip 2020 preferably engages finish taDer 2025 to form a
seal. This is readily achievable, since the .hread 2009 is
integrally molded with the finish portion 2Q01 that inc7udes the
inteqrally formed pushtabs 2007, vertical extenslons 2008 and finish
taDer 2025 while the thread 2018 is integrally formed with the
closure 2002 which includes pawls 2015 and seal lip 2020.
Figure 7A is a cross-sectional view of attachment 2100
taken along section line II-~I in figure 6. With pushtabs 2007 in
the position shown in Figures 7 and 7A, edges 2030 of vertical
extensions 2008 impede counter-clockwise rotation of pawls 2015
preventing attemPts to reopen the attachment by rotating the closure
2002 in the counter-clockwise direction indicated by the arrow "T~.
Clearance in channel 2011 between the outer surface of
thread collar 2017 and the inner surface of pushtabs 2007 noted as
dimension "X~ in Figure 7 permits sufficient inward deflection of
~ 93/07071 2 1 2 0 7 1 3 PC~r/US92/07286
pushtabs 2007 from the position shown in Figures 7 and 7A that the
vertical extensions 2008 will clear pawls 2015 when the user
concu~,ently depresses pushtabs 2007 and app1ies an unscrewing tor~ue
in the direction of arrow "T" to the closure 2002.
Figure 8 is a view of attachment 2100 taken at a point
corresponding to section line I-I of Figure 6, but with pushtabs 2007
deflected inwardly. In order to unscrew closure 2002 from finish
portion 2001 once the closure has been fully assembled, sufficient
manual pressure must be applied to opposed pushtabs 2007 in the
direction indicated by arrows P" in Figure 8 such that the vertical
extensions 2008 on pushtabs 2007 disengage the pawls 2015 on the
innermost surface of lock ring 2016 of closure 2002. The squeezing
force required to depress pushtabs 2007 is preferably great enough to
be difficult for a child, yet low enough that people using the
medication, such as arthritics, can readily depress the opposing
pushtabs 2007 while concurrently applying an unscrewing torque in the
direction of arrow "~" in Figure 8A to the closure 2002. The
preferred squeezing force "P" for the pushtabs 2007 to provide child
resistance without imposing undue difficulty for adults with impaire~
manual dexterity is believed to be within the range of about 0.5
pounds to about 5 pounds.
In addition. pushtabs 2007 are preferably substanttaily
flush with the outermost surface of tab ring or collar 2005 wnen tne
closure 2002 is fully secured in place so that simply grasping the
collar about its entire periphery and squeezing is unlikely to cermit
both of the vertical extensions 2008 on the opposed pushtabs 2007 to
become inadvertently disengaged from pawls 20I5 at the same time an
unscre~ing torque is being applied to the closure 2002. Rather. a
co~c~ decision to squeeze the opposing pushtabs 2007 must be made
by the user to initiate the opening process, and this must be
accompanied by a concurrent application of unscrewing torque to the
closure 2002 to proceed further. This minimizes the chance that a
child will be able to remove closure 2002 simply by squeezing the
entire periphery of tab collar 2005 in his or her hand while trying
to unscrew closure 2002.
Figure 8A is a cross-sectional view of attacnment 2100
taken at a point corresDonding to section line II-II of Figure 6, ~ut
WO g3/0707l 2 1 ~ ~ 71 3 PCr/US92/07286
18
showing the attachment 2100 in the condition shown in Figure 8, i.e.,
with pushtabs 2007 deflected inwardly. Vertical extensions 2008 are
thus shifted to a position wherein edges 2030 no longer impede
counter-clockwise rotation of paw1s 2015 on lock ring 2016 in the
direction indicated by the arrow "T" The user of child resistant
attachment 2100 is then able to further rotate closure 2002 in a
counter-clockwise direction, thereby causing the closure 2002 to rise
above vertical extensions 2008 and release the engagement of threads
2009 and 2018 on thread ring 2010 and thread collar 2017,
respectively. This permits closure 2002 to be completely removed
from finish portion 2001.
Figure 9 is a partially segmented side elevation view of
still another alternative embodiment 2500 of a child resistant
attachment of the present invention. However, as can be seen from
Figures 9 and 9A, finish portion 2501 of child resistant attachment
2500 is integrally molded as a single component with vial 2550.
Closure 2502 is shown unassembled from finish portion 2501 in Figure
9. A portion of the tab collar 2505 is shown partially segmented to
expose channel 2511 which accepts thread collar 2517 of closure 2502.
Tab ring or collar 2505 is interrupted by slots 2506 to form a pair
of opposed cantilevered spring-like pushtabs 2507. Pushtabs 2507
have vertical extensions 2508 which project above the plane of the
upper surface of tab collar 2505.
Figure 9A shows a cross-sectional view of child resistant
attachment 2500 and vial 2550 with closure 2502 in a fully assembled
condition, said view be taken through the opposed pushtabs 2507. The
lowermost end of attachment ring 2504 is integrally molded to the
u~ t end of vial 2550. Complementary threads 2509 and 2518 on
the outermost surface of thread ring 2510 and the innermost surface
of thread collar 2517, respectively, secure closure 2502 onto finish
portion 2501. Vertical extensions 2508 interlock with pawls 2515 on
the innermost surface of lock ring 2516. As with the embodiment of
Figures 6-8A, the finish portion 2501 is molded so that the vertical
extensions 2508 exhibit an unrestrained maximum exterior dimension
which is somewhat greater than the inside diameter of the closure
lock ring 2516. In general, operation of child resistant attachment
2 1 2 3 7 1 3 Pcr/US92/07286
19
2500 is similar to that described for chi7d resistant attachment
2100.
It is believed that the pac~age designs, attachment designs
and processes described herein and their intended advantages will be
understood from the foregoing description. It will, of course, be
apparent to those skilled in the art that various changes may be made
in form, construction, and arrangement without departing from the
spirit and scope of the invention and it is intended to cover in the
appended claims all such modifications that are within the scope of
I0 this invention.
