A child-resistant package consists of a container having an open-ended neck and a cap having a top and an annular skirt which telescopes over the container neck. There are co-operating snap-over retainers on the exterior of the neck and the interior of the cap skirt which require the cap to be moved axially a distance greater than the axial over-lap of the retainers in order to remove the cap. The container neck and the cap skirt also have a radially extending lug and a circumferentially extending ramp that are moved into engageable alignment by flexing the cap skirt inwardly. The ramp has a surface which is inclined relative to the axis of the neck and cap skirt and which has an axial height greater than the distance of axial over-lap of the retainers. In order to remove the cap, the skirt is flexed inwardly to align the lug with the ramp surface and the cap is rotated relative to the container neck causing the cap to be moved axially a distance sufficient to disengage the over-lapped retainers. A stop bar is formed near the beginning end of the ramp which is spaced circumferentially from the ramp a distance only slightly greater than the circumferential width of the lug so that the lug must be inserted into such space when the skirt is flexed inwardly in order to engage the lug with the ramp when the cap is rotated relative to the container for removing the cap.

This invention relates to container closures and more particularly to 
child-resistant or child-proof container and enclosure combinations. 
Although many dozens of child-resistant or so-called "child-proof" 
container closures or combinations of containers and closures have been 
suggested and many patents have issued on those devices, relatively few 
have been successful in the market place. 
Some of the devices have been much too complicated so that the cost to 
manufacture them has been prohibitive. Others have failed the tests under 
the protocol of the Poison Prevention Packaging Act of 1970 because it has 
been possible for a small child to gain access to the contents of a 
container having a supposedly child-resistant closure where the closure 
was of such size and operated in such fashion that the child could bite 
the closure and hold the container in its hands to either pry off the 
closure or turn it to unscrew it from the neck of the container. 
While some successful child-resistant closures have consisted of two 
separately molded parts such as a screw cap and an overcap which must be 
properly manipulated in order to provide for unscrewing the screw cap, 
these two-part closures are more expensive than single piece closures 
because two separate molds are required for their production and the two 
parts must be assembled to each other before they can be delivered to the 
location where the containers are filled and the caps are placed on the 
containers. 
In the experience resulting from the design and testing of closures and 
combinations of closures and containers intended to be child-resistant it 
has been found that the most effective arrangements are those in which two 
distinctively different movements must be made in order to open the 
package, i.e., to remove the closure. 
It is, therefore, the principal object of the instant invention to provide 
a child-resistant package for pharmaceuticals, household chemicals and 
other potentially harmful substances consisting of a container having an 
open-ended neck and a one-piece closure having means which cooperate with 
the elements of the neck to make the package child-resistant. 
It is yet another object of the instant invention to provide a 
child-resistant package comprising a closure of the type generally 
referred to as "squeeze and turn" in which the container neck and the 
closure have co-operating rib means for retaining the closure on the 
container neck and which also have co-operating means that are engageable 
by deforming the skirt of the cup-shaped closure radially inwardly to 
bring these latter means into circumferential alignment so that subsequent 
rotation of the closure relative to the container neck will result in 
disengaging the rib means and removal of the closure. 
Yet another important aspect of the instant invention resides in the fact 
that the co-operating means on the container neck and on the skirt of the 
closure cannot be circumferentially aligned with each other so as to 
result in the closure being forced upwardly by its subsequent rotation 
except when certain indicia on the container and the closure are aligned 
with each other, this alignment being perceptible to an older child or an 
adult. 
The objects of the invention are accomplished by a child-resistant package 
wherein a container has a body and a tubular open-ended neck joined to the 
body, a cup-shaped closure for the neck having an annular skirt adapted to 
be telescoped over the neck, retainer means on the neck and the skirt for 
retaining the closure in closed position on the neck during relative 
rotation of the closure and the container, the retainer means being 
disengagable by axial movement of the closure relative to the neck. A pair 
of elements are formed on the outer surface of the neck and the inner 
surface of the skirt, respectively, with the elements having a radial 
thickness such that they do not engage each other when the closure is 
rotated on the neck with the skirt in its normal annular configuration. A 
first of the elements has a ramp surface extending angularly and 
circumferentially an axial distance greater than the distance of axial 
movement required to disengage the retainer means and a second of the 
elements is positioned at an axial level for engagement with the ramp 
surface of the first of the elements when the skirt is flexed radially 
inwardly and the closure is rotated to cause the closure to move axially 
to disengage the retainer means. A guard element is formed on the same 
surface as the first of the elements and is spaced therefrom a 
circumferential distance only enough to provide a keyway for the radial 
insertion of the second of the elements when the skirt is flexed radially 
inwardly. Unless exact alignment is first achieved, the subsequent 
squeezing and rotations of the cap is ineffective to open the container.

The invention is embodied in a package, a portion of which is indicated at 
10 in FIGS. 1 through 5. The package 10 includes a container 12 and a 
closure 14. The container 12 has a tubular open-ended neck 16 and an 
inverted cup-shaped closure or cap 18 that is adapted to telescope over 
and close the open end of the container neck 16. The closure or cap 18 
preferably is made of a plastic material and has a disc-like top 20 and a 
cylindrical stiffly flexible skirt 22. The container neck 16 has a 
continuous annular bead 24 which cooperates with a plurality of uniformly 
spaced tab elements 26 on the inner wall of the skirt 22. As shown in FIG. 
6 at least four uniformly spaced tab elements are preferred. The tab 
elements 26 extend radially inwardly and have inclined upper and lower cam 
surfaces 28 and 30, respectively, which are adapted to engage the bead 24 
during closing and opening of the package 10. The outer diameter of the 
apex of the bead 24 and the radial inner edges of the tab elements 26 are 
selected of a dimension to interfere with each other. When the closure 14 
is placed on the neck 16, the lower cam surfaces 30 engage the bead 24 to 
distort the skirt 22 sufficiently so that the closure 14 can move axially 
relative to the neck 16 until the upper cam surfaces 28 engage the annular 
surface 32 at the underside of the bead 28. When the cap is removed the 
upper cam surface coacts with the bead 24 to distort the skirt 22 
sufficiently so that the closure 14 can be moved axially relative to the 
container 12 for removal or opening of the package 10. 
When the closure 14 is in its closed position as illustrated in FIG. 3 it 
is extremely difficult to pull the closure 14 from the neck 16. Also, the 
bead 24 and the cooperating tab elements 26 permit the closure 14 to be 
rotated relative to the neck 16 but still retain the closure in position 
to close the open end of the neck 16. In addition, the lower lip 34 of the 
skirt 22 extends downwardly into closed adjacent relationship to a 
shoulder 36 formed between the neck 16 and the remainder of the body of 
the container 12. Preferably the lip 34 is spaced sufficiently to permit 
rotation of the closure 14 relative to the neck 16 but at the same time 
prevents the insertion of a tool by which the closure 14 might be pried up 
to disengage the tab elements 26 from the bead 24. 
Removal of the closure 14 from the neck 16 requires relative axial 
displacement and the amount of such axial displacement is determined by 
the axial length of the tab elements 26 and more particularly to the axial 
length of the upper cam surface 28 and the distance between the upper and 
lower cam surfaces 28 and 30. The means for effecting the axial 
displacement of the closure 14 that is required to open the container 12 
includes a circumferentially extending ramp element 38 located on the 
outer surface of the container neck 16 and against the shoulder 36. 
Preferably a pair of such ramp elements 38 is employed and are disposed at 
diametrically opposite sides of the container neck 16. The ramp elements 
38 each have a ramp or guide surface 40 which extends from the shoulder 36 
an axial distance slightly greater than the distance that the closure 18 
must be moved axially to disengage the tab elements 26 from the bead 24. 
The interior surface of the closure 14 is provided with a pair of radially 
inwardly extending lugs or ribs 44 with bottom end portions 46 adapted to 
engage the guide or ramp surface 40 during rotation of the closure 14 
relative to the neck 16. The lugs 44 can extend the full axial length of 
the interior of the closure 14 as seen in FIG. 2 and each incorporate one 
of the tab elements 26. Preferably there are two such ribs 44 on the inner 
surface of the skirt 22 of the closure 14 which are diametrically opposed 
to each other. 
The ramp elements 38 having an outer circumferential surface 45 with a 
radius slightly less than the spacing between the diametrically opposed 
ribs 44 so that the closure 14 is freely rotatable on the container 16. As 
a result, mere rotation of the closure 14 is not effective to bring about 
removal of the closure 14 from the neck 16. 
In order to remove the closure 14 from the neck 16 two motions are 
required. It is necessary first to squeeze the flexible skirt 22 of the 
closure 14 at diametrically opposed points opposite the ribs 44. This 
flexes the skirt 22 and the ribs 44 inwardly toward each other as best 
seen in FIGS. 4 and 5 so that the lower ends 46 of the ribs 44 engage and 
are moved into circumferential alignment with the guide surfaces 40 on the 
ramp elements 38. Subsequent rotation of the closure 14 through a few 
degrees while the skirt 22 is maintained in its deflected position serves 
to force the ribs 44 up the full length of the relatively short ramp 40 
and force the closure 14 axially a sufficient distance to disengage the 
tab elements 26 from the bead 24. 
Although the requirement for inward flexure of the skirt 22 and subsequent 
rotation of the closure 14 renders the package reasonably child-resistant, 
the present embodiment of the invention has additional safety features. As 
best seen in FIG. 2, a guard or stop 50 is located on the exterior of the 
neck 16 and in circumferentially spaced relationship the lower end or 
beginning portion of the ramp surface 40 of the ramp elements 38. The 
stops 50 are spaced away from the lower edge of the guide surfaces 40 a 
distance only slightly greater than the circumferential extent of the ramp 
engaging ribs 44. Consequently, the spacing between the stop 50 and the 
beginning of the guide surface 40 forms a space or keyway 52 into which 
the ribs 44 must be deflected to bring about the necessary alignment so 
that subsequent rotation of the closure 14 can move it axially relative to 
the neck. In the event that the ribs 44 are not aligned with the keyways 
52, deflection of the skirt 22 and subsequent rotation of the closure 14 
will result in the ribs 44 coming into engagement with either the stop 50 
or an end 54 of the ramp element 38 opposite to the ramp 40. In the 
absence of deflection of the skirt 22, the closure 14 is permitted to 
rotate because of the clearance provided between the ribs 44 on the 
closure 14 and the outer circumferential surfaces of the stop 50 and ramp 
element 38. 
Instructions relative to removal of the closure 14 from the neck 16 can be 
in the form of a legend appearing on the closure top 18 as illustrated in 
FIG. 1. 
To facilitate alignment of the closure 14 with the container 12, arrow 56 
on the container 12 and 58 on the closure 16 are provided which when 
aligned vertically, insure that the ramp engaging ribs 44 will be 
positioned radially opposite the keyways 52. Subsequent flexing of the 
skirt 22 will bring the ribs 44 into circumferential alignment with the 
guide or ramp surfaces 40 so that subsequent rotation of the closure 14 
will cause the ribs 44 to ride up the ramp surfaces 40 to cause axial 
movement of the closure 14 relative to the neck 16 and disengagement of 
the bead 24 and the top elements 26. 
If a younger child endeavors to squeeze the closure skirt 22 radially 
inwardly, for example, even by biting it and then rotating the closure 
relative to the container, the odds are that the ramp engaging ribs 44 
will engage the stops 50 or the stop surface 54 of the ramp elements 38. 
It is only upon precise alignment of the indicia 56 and 58 by one capable 
of reading the instructions on the top of the closure 14 that proper 
alignment for engagement of the ribs 44 with the ramp elements 38 can be 
achieved. 
Another embodiment of the invention is illustrated in FIGS. 7 through 10 
which correspond to FIGS. 2 through 5 illustrating the first embodiment of 
the invention. In FIGS. 7 through 9, like parts have been identified with 
the same reference characters. The principal differences are that a pair 
of ramp elements 68 and a pair of guard elements 70 corresponding 
substantially to the ramp elements 38 and guard elements 50, respectively, 
of the first embodiment of the invention are formed on the interior 
surface of the closure 18 instead of on the outer surface of the neck 16. 
Also, the lugs or ribs 44 are replaced by short lug or rib elements 72 
disposed on the shoulder 76 formed at the juncture of the neck of the 
container 12. In all other respects, the second embodiment of the 
invention is the same in construction as the first embodiment. Also, 
operation is substantially identical in that opening of the package 10 
first requires alignment of the indicia arrows 56 and 58 followed by the 
subsequent radial inward squeezing of the skirt 22 of the closure 14 to 
move the ramp elements 68 radially inwardly so that rib elements 72 are 
received in the keyway 52a. Subsequent rotation of the closure 14 in a 
counter-clockwise direction brings the rib elements 72 into engagement 
with the ramp elements 68 and forces the closure 14 axially of the neck 16 
to release tabs 26 from the bead 24 for removal of the closure. 
A childproof closure and container combination has been provided in which 
at least two distinctive motions are required to afford removal of the 
closure from the container. These motions are the squeezing and flexing of 
the closure skirt followed by rotation of the closure. However, even 
before these two motions occur, it first is necessary to properly align 
the closure and the container visually pursuant to instructions presented 
by a legend on the package.