Liquid-proof Safety Closure

Abstract

A safety closure cap/container combination includes co-operating lugs and cam surfaces on the outer surface of the container neck and the inner surface of the side wall of the cap to provide relative axial movement of the cap toward the container on rotation of the cap in a tightening direction and relative separation of the cap and the container on rotation of the cap in the opposite direction. Detent notches in the cam surfaces serve to retain the cap in its closed position and to require both axial movement and rotation of the cap for its removal from the container. A cap liner is provided within the cap for sealing engagement with the end of the container neck. A set of fingers is integrally formed with the end wall of the cap to press against the cap liner and to be flexed upwardly on tightening of the cap on the container so as in turn to maintain the liner in sealing engagement with the end of the container neck. Aligned openings are provided in the end wall of the cap to facilitate manufacture.

Description

BACKGROUND OF THE INVENTION

The present invention relates to safety closure caps and closure cap/container combinations and more particularly to safety closure caps intended to provide a positive sealing action on the open ends of containers on which such caps are removably disposed.

Numerous proposals have heretofore been made for the construction of so-called child-proof closures for the purpose of reducing the accidental poisoning of children by drugs, toxic household products and other harmful substances. Many of the previously proposed safety closures have proven to be commercially impractical due to their relatively high manufacturing costs resulting in turn from their relatively complex designs. Others of the previously proposed safety closures, while reasonably effective for sealing containers containing solid products, such as tablets, pills, etc., have proved practically useless for liquid containers with which a positive sealing action is required between the closure and the neck of the container. This same difficulty also arises with containers for some solid products when the lack of a satisfactory seal can result in contamination, oxidation or other degradation of the product within the container.

The design of safety closures is generally a matter of compromise between creating a closure which is sufficiently difficult to remove from a container to reduce the risks of its removal by a young child while such removal should not be so difficult as to make the removal too difficult for an adult, for example, an elderly or arthritic person. Many of the previously proposed safety closures have presented the further disadvantage that they have been relatively difficult to manufacture on a large scale production basis to give a consistent ease of opening. Minor variations in the manufacturing tolerances frequently led with the known safety closures to considerable variation in their ease of opening with the result that some could be opened by young children while others were too difficult for even healthy adults to open. It is generally accepted that a safety closure requires two different movements of the closure relative to the container in order to allow the closure to be released from its locked position.

It is a principal object of this invention to provide a closure cap which is not only exceedingly simple in its construction but which is also characterized by a relatively consistent operating performance when manufactured by modern mass production techniques.

Another important object of this invention is to provide a safety closure cap which is effective to ensure a positive sealing closing of a container so that such a closure cap can be used with confidence on containers of liquid or degradable materials.

Yet another object of this invention is to provide a safety closure of the aforementioned type and which requires axial movement of the closure toward the container on which it is disposed before the closure can be rotated into a released position thereof.

Other objects of the invention will become apparent as the description herein proceeds.

SUMMARY OF THE INVENTION

Broadly, the present invention provides a closure cap including an end wall and a side wall depending therefrom, said side wall having a generally cylindrical inner surface, tightening means on said inner surface of said side wall for engagement with co-operating means on an outside peripheral surface of a neck wall of a container for causing relative axial closing movement of said cap on such a container into a closed position thereon on relative rotation of said cap and the container in one direction and relative axial separation of the cap and such a container into a released position of said cap on relative rotation on said cap and the container in an opposite direction, manually releasable detent means associated with said tightening means for retaining said cap in its closed position on the container, a cap liner disposed within said cap for disposition between said end wall of said cap and an end surface of the neck wall of the container on which said cap is disposed, and a resiliently deformable biasing means within said cap for axially biasing said cap liner into sealing engagement with the end surface of the neck wall of the container when said cap is rotated on the neck of such a container into its closed position.

The present invention also embraces the combination of a container and a closure cap releasably securable on said container, in which said container includes a neck wall and in which said closure cap comprises an end wall and a side wall depending therefrom, said side wall having a generally cylindrical inner surface, tightening means on said inner surface of said side wall for engagement with co-operating means provided on an outside peripheral surface of said neck wall of said container for causing relative axial closing movement of said cap on said container into a closed position thereon on relative rotation of said cap and said container in one direction and relative axial separation of said cap and said container into a released position of said cap on relative rotation of said cap and said container in an opposite direction, manually releasable detent means associated with said tightening means for retaining said cap in said closed position thereof on said container, a cap liner disposed within said cap between said neck wall of said container and said end wall of said cap, and a resiliently deformable biasing means within said cap for axially biasing said cap liner into sealing engagement with said end surface of said neck wall of said container when said cap is disposed on said container in said closed position thereof.

As will be explained in greater detail hereinafter, the aforementioned resiliently deformable biasing means provided in a closure cap in accordance with this invention can be provided as an integral part of the cap itself. Alternatively, such a resiliently deformable biasing means can be provided as an integral part of the cap liner provided in such a closure cap.

Other features and advantages of the invention will become apparent as the description herein proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described merely by way of illustration with reference to the accompanying drawings in which:

FIG. 1 is an exploded perspective view from below showing one embodiment of a closure cap in accordance with this invention with the cap liner thereof shown removed from within the cap and fragmentarily showing a container neck on which the closure is intended to be used;

FIG. 2 is a perspective view from above of the closure cap of FIG. 1;

FIG. 3 is a vertical axial sectional view through the cap/container combination of FIG. 1 showing the closure cap thereof removed from the neck of the container, the container being shown in side elevation;

FIG. 4 is a vertical axial sectional view similar to that of FIG. 3 but showing the closure cap disposed on the neck of the container and rotated thereon into its closed position but prior to the engagement of a detent means which is provided on the closure;

FIG. 5 is a vertical axial sectional view similar to those of FIGS. 3 and 4 but showing the closure cap in its closed position with the detent means operative to prevent releasing rotation of the cap from the container;

FIG. 6 is a perspective view from above of another embodiment of a closure cap in accordance with this invention;

FIG. 7 is a fragmentary vertical sectional view through the closure cap of FIG. 6 when viewed as indicated by the arrows 7--7 of that figure;

FIG. 8 is a vertical axial sectional view similar to that of FIG. 3 but showing another alternative embodiment of a closure cap in accordance with this invention;

FIG. 9 is a vertical axial sectional view similar to that of FIG. 4 but showing the closure cap/container combination of FIG. 8 with the cap rotated on the container into its closed position but prior to the engagement of a detent means which is provided in the combination;

FIG. 10 is a vertical axial sectional view similar to that of FIG. 5 but illustrating the cap/container combination of FIG. 8 after engagement of the detent means;

FIG. 11 is a vertical axial sectional view similar to that of FIG. 5 but showing the additional and optional provision of lugs in the closure cap of FIGS. 1 to 5 for the purpose of retaining a cap liner within the cap;

FIG. 12 is a horizontal sectional view through the closure cap of FIG. 11 when viewed as indicated by the arrows 12--12 of that figure;

FIG. 13 is a vertical axial sectional view through another embodiment of a closure cap in accordance with this invention;

FIG. 14 is a vertical axial sectional view through yet another embodiment of a closure cap in accordance with this invention;

FIG. 15 is an exploded view of another embodiment of a closure cap/container combination in accordance with this invention; and

FIG. 16 is a vertical axial sectional view through the cap/container combination of FIG. 15 showing the cap disposed on the container in a released position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will first be made to the closure cap/container combination illustrated in FIGS. 1 to 5 of the accompanying drawings. The combination illustrated in those particular figures comprises a closure cap generally indicated at 10 and which is intended to be used for closing a container generally indicated at 12 and having a neck generally indicated at 13. The cap 10 itself includes an end wall 14 and integrally formed therewith a side wall 15 having a cylindrical inner surface 16. The closure cap 10 also includes a cap liner 18.

Three equiangularly spaced apart cam surfaces 20 are provided in obliquely extending slots 21 formed in the inner surface 16 of the cap side wall 15. Axially oriented slots 23 extend from the lower ends of the slots 21 to the bottom edge of the side wall 15. Corresponding equiangularly spaced apart lugs 24 are provided on the neck wall 13 of the container 12 and, as will be readily understood by reference to FIGS. 4 and 5, these lugs 24 are introduced through corresponding ones of the slots 23 into the respective slots 21 for tightening engagement with the cam surfaces 20 on relative rotation of the cap 10 and the container 12. The cam surfaces 20 and the lugs 24 together constitute a tightening means.

As already indicated, a closure cap in accordance with this invention also comprises a detent means for releasably retaining the cap 10 in its closed position as shown in FIG. 5. In the structure shown in FIGS. 1 to 5, such detent means comprises notches 25 formed in the cam surfaces 20 generally near the upper ends of the latter surfaces.

Referring particularly to FIGS. 2 and 3, it will be seen that the end wall 14 of the cap 10 is integrally formed with a plurality of fingers 28 which normally extend obliquely downwardly and radially outwardly from the end wall 14 toward the side wall 15 of the cap 10. The cap 10 including the fingers 28 is formed from an appropriate resiliently flexible material and the released or unflexed positions of the fingers are as shown in FIG. 3. Each of the fingers 28 is associated with a corresponding aligned opening 29 in the end wall 14 to facilitate the moulding of the cap 10 as a unitary structure. The fingers 28 are resiliently upwardly flexed toward the end wall 14 by the neck wall 13 of the container 12 acting through the cap liner 18 as the lugs 24 travel upwardly along the cam surfaces 20 of the slots 21 on rotation of the cap 10 on the container neck 13 in a tightening direction, i.e. clockwise when viewed from above for the particular structure illustrated.

It will also be understood that, as the fingers 28 are increasingly flexed upwardly on continued tightening rotation of the cap 10, increasing pressure will be applied by those fingers to the cap liner 18 to ensure positive sealing between the cap liner 18 and the neck wall 13. When the lugs 24 generally reach the top ends of the cam surfaces 20, the bearing action of the fingers 28 causes the lugs 24 to be received in the detent notches 25. The resulting limited axial separation of the cap 10 and the container 12 allows some relaxation of the flexing of the fingers 28 but the notches 25 are so dimensioned that, even after such separation, the fingers 28 are still effective to apply sufficient pressure to the cap liner 18 to ensure effective sealing as shown in FIG. 5.

It will further be understood that, when it is desired to remove the closure cap 10 from the container 12, i.e. from the closed position shown in FIG. 5, it is necessary to apply downward pressure to the cap 10 to cause upward flexing of the fingers 28 at least partially into the openings 29 while the lugs 24 are displaced from the detent notches 25. With the lugs 24 so displaced, the cap 10 must then be rotated in an anti-clockwise direction (viewed from above) until the cap 10 can be bodily removed from the container 12 in an axially upward direction with the lugs 24 passing along the slots 23.

The thickness of each of the fingers 28 will be determined by the resilience of the material from which the cap is formed as well as by the desired resilient stiffness of those fingers. According to the thickness of the fingers 28, they may be flexed upwardly merely toward the end wall 14 or they may be flexed at least partially into the corresponding openings 29 on rotation of the cap 10 into its closed position as actually shown in FIGS. 4 and 5. It will also be understood that the invention is not restricted to the provision of any particular number of fingers 28 and openings 29 and that, in practice, such number will be determined by such factors as the thickness of the end wall 14, the resilience of the material from which the cap 10 is formed, the desired sealing pressure on the liner 18, and the required difficulty for releasing the cap from the container. It will further be appreciated that the cap 10 complies with the generally accepted criterion of requiring two independent movements of that cap to release it from its closed position.

An alternative construction for a closure cap in accordance with this invention is shown in FIGS. 6 and 7 of the accompanying drawings. Those figures show a closure cap generally indicated at 30 and including an end wall 31 and a side wall 32. Integrally formed and resiliently upwardly flexible fingers 33 are provided on the end wall 31 and corresponding aligned openings 34 are provided in the end wall 31 for the fingers 33. The closure cap 30 differs from the cap 10 shown in FIGS. 1 to 5 only in that the fingers 33 project around the axis of the cap slightly inwardly of its side wall 32 instead of generally radially outwardly from such axis as was the case for the cap 10.

Referring now to FIGS. 8, 9 and 10 of the accompanying drawings, it will be noted that there is illustrated therein generally at 35 a closure cap including an end wall 36 and a side wall 37. The closure cap 35 also includes a flexible cap liner 38 which is secured to the undersurface of the end wall 36 by an integrally formed generally central boss 39. The cap 35 is shown in FIGS. 8 to 10 as being used as a closure for a vial-type container generally indicated at 40 and including a wall 41. The tightening and detent means provided on the cap 35 and the vial wall 41 are generally identical to those already described herein with reference to FIGS. 1 to 5 and comprise outwardly projecting lugs 42 formed on the vial wall 41 and cam surfaces 43 formed in angularly spaced apart obliquely oriented slots 44 formed in the inner surface of the cap wall 37, axially oriented slots 45 and detent notches 46 being provided at opposite ends of the slots 44.

Generally radially disposed resiliently flexible fingers 48 are integrally formed with the end wall 36 of the cap 35 and each such finger has associated therewith a corresponding aligned opening 49 in the end wall 36. In accordance with another useful feature of this invention, the fingers 48 and the central boss 39 are dimensioned so that the cap liner 38 is deformed so as to be slightly upwardly convex when the cap 35 is removed from the container 40 and slightly upwardly concave when the cap 35 is tightened on the container 40 but before the lugs 42 are received in the detent notches 46 so that, when the lugs 42 are actually received in those notches 46, the liner 38 assumes a generally planar non-deformed configuration as shown in FIG. 10.

The closure cap generally indicated at 50 in FIG. 11 is essentially identical to that already described herein with reference to FIGS. 1 to 5 in that it includes an end wall 51 and a side wall 52, resiliently flexible fingers 53 being integrally formed with the end wall 51 which is also formed with corresponding aligned openings 54. The cap 50 is shown as being formed with tightening slots 55 and detent notches 56 for co-operation with outwardly projecting lugs 57 formed on the neck of a vial 58 on which the cap 50 is disposed.

The side wall 52 of the cap 50 is provided with three angularly spaced apart lugs 60 which extend radially inwardly for the purpose of retaining a cap liner 61 within the cap 50 even when the latter is removed from the vial 58. It will be understood that the lugs 56 on the vial wall 58 will be larger in the radial direction than the lugs 60 so that the former can be received in the slots 55.

The closure caps hereinbefore described with reference to FIGS. 1 to 11 are particularly suited to manufacture with unitary cap structures by modern high speed injection moulding techniques.

The closure cap generally indicated at 62 in FIG. 13 of the accompanying drawings includes an end wall 63 and a side wall 64 in the inner surface of which there are formed equiangularly spaced apart tightening slots 65 including detent notches 66 which function in precisely the same manner as the corresponding tightening and detent means already described herein with reference to the preceding figures of the drawings. The closure cap 62 also includes a cap liner (not shown) and differs from the previously described caps in that, instead of resiliently flexible fingers, there is provided a resiliently flexible skirt 68 which is suitably secured as at 67 to a central boss 69 integrally formed with the end wall 63 generally centrally in the undersurface thereof.

The closure cap generally indicated at 70 in FIG. 14 is similar to the cap 62 of FIG. 13 and identical components of the two caps are identified by the same legends. The cap 70 differs from the cap 62 only in that, instead of the skirt 68, the skirt of the former is radially segmented so as effectively to provide a plurality of resiliently flexible fingers 71 radially outwardly and downwardly projecting from a central hub 72 suitably secured as at 73 to a generally central boss 74 integrally formed with the end wall 63 on the undersurface thereof.

Reference will finally be made to the closure cap generally indicated at 80 in FIGS. 15 and 16 of the accompanying drawings and shown as being intended for use on a vial generally indicated at 81. The combination illustrated in FIGS. 15 and 16 differs primarily from those already described herein with reference to the preceding figures of the accompanying drawings in that the resiliently deformable biasing means which are provided to ensure positive sealing engagement of a cap liner generally indicated at 82 with a top surface of a wall 83 of the vial 81 are provided as part of the liner 82 instead of as an integral part of the cap 80.

The cap 80 includes an end wall 84 and a side wall 85 which has a generally cylindrical inner surface 86 from which three equiangularly spaced apart lugs 87 extend inwardly for co-operative engagement with undersurfaces 88 of cam members 89 formed on the outer surface of the vial wall 83, notches 90 being formed in the cam members 89 to provide the necessary detent means. Three equiangularly spaced apart lugs 92 project from the inner surface 86 of the side wall 85 of the cap 80 to retain the cap liner 82 within the cap 80 although the provision of such additional lugs 92 is not essential even when a captive liner is required since such a function is also provided by the lugs 87.

Referring now in greater detail to the structure of the cap liner 82, it will be seen that it includes a generally disc-like member 94 which is integrally formed in its upper surface with an outwardly flaring and resiliently flexible skirt 95. On tightening rotation of the cap 80 on the vial 81, engagement of the lugs 87 along the cam surfaces 88 causes radially outward flaring of the skirt 95 of the cap liner 82 which in turn causes a positive seal between the liner 82 and the neck of the vial 81 and engagement of the lugs 87 in the detent notches 90. When it is desired to remove the cap 80 from the vial 81, it is necessary to apply axially downward pressure on the cap 80 to displace the lugs 87 from the detent notches 90 prior to rotating the cap 80 in the counter-clockwise direction.

It will be understood that the closure caps of this invention can be formed from a wide range of materials although the use of plastics materials such as polystyrene and polypropylene has proved to be particularly effective. The liners provided in such caps can similarly be formed of a plastics material although the use of paper products which can be laminated with metallic or plastic foils is not precluded. In the case of the structures shown in FIGS. 15 and 16, the liner must naturally, however, have the necessary degree of flexible resilience.

It will further be understood that the tightening means and the detent means provided on a closure/container combination in accordance with this invention will be dimensioned and designed to take into due account the actual resilience of the selected deformable biasing means, such as the skirt 68 shown in FIG. 13, so as to provide the desired degree of difficulty for releasing the detent means and so as to ensure the desired degree of sealing between the cap liner and the container.

Claims

What is claimed is:

1. A closure cap which comprises an end wall and a side wall depending therefrom, said side wall having a generally cylindrical inner surface, tightening means on said inner surface of said side wall for engagement with co-operating means on an outside peripheral surface of a neck wall of a container for causing relative axial closing movement of said cap on such a container into a closed position thereon on relative rotation of the cap and the container in one direction and relative axial separation of the cap and such a container into a released position of said cap on relative rotation of said cap and the container in an opposite direction, manually releasable detent means associated with said tightening means for retaining said cap in its closed position on the container, a cap liner disposed within said cap for disposition between said end wall of said cap and an end surface of the neck wall of the container on which said cap is disposed, and a resiliently deformable biasing means within said cap and comprising a plurality of fingers integrally formed with said end wall of said cap and extending obliquely and axially away from said end wall within said cap for axially biasing said cap liner into sealing engagement with the end surface of the neck wall of the container when said cap is rotated on the neck of the container into its closed position, each said finger being aligned with a corresponding opening in said end wall whereby, on rotation of said cap into said closed position thereof on the container, said fingers are resiliently flexed toward said end wall of said container.

2. A closure cap as claimed in claim 1 in which each said finger is resiliently flexed into said corresponding opening in said end wall of said cap on rotation of said cap into its closed position on the container.

3. A closure cap as claimed in claim 1 in which each said finger extends axially away from said end wall within said cap and generally radially outwardly therefrom toward said side wall.

4. A closure cap as claimed in claim 1 in which said fingers are disposed generally circularly on said end wall of said cap about an axis thereof so as to project axially therefrom within said cap.

5. A closure cap as claimed in claim 1 in which said cap liner is secured to said end wall of said cap through a central boss integrally formed with said end wall whereby said cap liner is deformed into an outwardly convex configuration on rotation of said cap on the container into its closed position and then resiliently restored into an essentially non-deformed generally planar configuration as said detent means permits limited axial separation of said cap and said container.

6. A closure cap as claimed in claim 1 in which said tightening means comprises a plurality of cam surfaces formed in said inner surface of said side wall of said cap and in which said detent means comprises a corresponding plurality of notches formed in said cam surfaces whereby, on engagement of said cam surfaces by outwardly projecting lugs formed on the neck wall of the container and on relative rotation of said cap and such a container, said cap is caused to move axially toward the neck wall of the container into said closed position of said cap and whereby, on movement of such lugs into said notches, said cap is retained on the container being releasable therefrom only by the application of axial pressure to the cap to cause the lugs to be moved out of said notches.

7. A closure cap as claimed in claim 6 in which said side wall of said cap is integrally formed with generally radially inwardly extending and angularly spaced apart lugs for retaining said cap liner within said cap.

8. A closure cap as claimed in claim 1, in which said tightening means comprises a plurality of cam surfaces formed in said inner wall surface of said side wall of said cap and in which said detent means comprises a corresponding plurality of notches formed in said cam surfaces whereby, on engagement of said cam surfaces by outwardly projecting lugs formed on the neck wall of the container and on relative rotation of said cap and such a container, said cap is caused to move axially toward the neck wall of the container into said closed position of said cap and whereby, on movement of such lugs into said notches, said cap is retained on the container being releasable therefrom only by the application of axial pressure to the cap to cause the lugs to be moved out of said notches.

9. In combination, a container and a closure cap releasably securable on said container, in which said container including a neck wall, said closure cap comprising an end wall and a side wall depending therefrom, said side wall having generally cylindrical inner surface, and there also being provided tightening means on said inner surface of said side wall for engagement with co-operating means provided on an outside peripheral surface of said neck wall of said container for causing relative axial closing movement of said cap on said container into a closed position thereon on relative rotation of said cap and said container in one direction and relative axial separation of said cap and said container into a released position of said cap on relative rotation of said cap and said container in an opposite direction, manually releasable detent means associated with said tightening means for retaining said cap in said closed position thereof on said container, a cap liner disposed within said cap between said neck wall of said container and said end wall of said cap, and a resiliently deformable biasing means within said cap and comprising in turn a plurality of fingers integrally formed with said end wall of said cap and extending axially and obliquely away from said end wall of said cap within said cap for axially biasing said cap liner into sealing engagement with said end surface of said neck wall of said container when said cap is disposed on said container in said closed position thereof, each said finger being associated with a corresponding aligned opening in said end wall thereby, on rotation of said cap into said closed position on said container, said fingers are axially flexed toward said end wall.

10. A combination as claimed in claim 9, in which said tightening means comprises a plurality of cam surfaces formed on said side wall of said cap and corresponding lugs formed on said neck wall and in which said detent means comprises a corresponding plurality of notches formed in said cam surfaces for receiving respective ones of said lugs when said cap is disposed in said closed position thereof whereby, on movement of said lugs into said notches, relative rotation of said cap and said container is prevented until said lugs are displaced from within said notches by the application of axial pressure to said closure cap.

11. A combination as claimed in claim 9 in which said side wall of said cap is integrally formed with inwardly extending and angularly spaced apart lugs for retaining said cap liner within said cap.

12. A combination as claimed in claim 9 and in which said side wall of said cap is integrally formed with inwardly extending and angularly spaced apart lugs for retaining said cap liner within said cap.