Safety Closure For Containers

Abstract

A safety closure including a base member having a spout, an annular shoulder around the spout, and a peripheral ridge protruding from the shoulder, a cover member having a domed crown with a skirt depending therefrom, a plurality of stacking bosses protruding from the outer surface of the crown and a segmented ring protruding from the inner surface of the crown, and a hinge interconnecting the base member and the cover member and having a weakened portion of reduced cross section adjacent the cover member, the cover member being adapted to be disposed on the base member with the segmented ring engaging a top surface of the spout and a peripheral bottom edge of the skirt captured by the ridge whereby the cover member can be removed from the base member only by depressing the crown to free the peripheral bottom edge.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to safety closures for containers and, more particularly, to such closures which cannot easily be opened by children or those uninstructed in the method of opening and which are not subject to accidental opening.

2. Dicussion of the Prior Art

There is a great need for simple and inexpensive closures which are adaptable for mass production and which cannot be easily opened by children or those without prior knowledge as to the manner in which such closures are opened and are not subject to accidental opening. The requirement for such safety closures is of extreme importance for use with containers for volatile or otherwise harmful products in that children must be prevented from access to such products and access to such products and exposure of such products due to accidental opening of such closures must be prevented.

In the past, many safety closures have been proposed; however, to date none of the proposed safety closures have satisfied both the requirements of high safety in the prevention of accidental opening and the prevention of opening by children as well as being economically manufactured. Children will normally use all available means to open a container; and accordingly, an acceptable safety closure must be constructed to prevent opening by means of sharp objects used to pierce the closure or to pry the closure loose as well as to prevent opening by utilizing the teeth to grip the closure to pry it open or by biting with the sharp edge of the teeth to open the closure. Accidental opening may occur due to pressure on the closures during stacking for storage and shipment as well as by dropping the containers on hard surfaces or catching a portion of the closure on a sharp object.

U. S. Pat. Nos. 3,398,848, 3,434,614 and 3,484,016 are illustrative of prior art attempts to provide a safety closure meeting the above mentioned requirements; however, while the closures of these patents all require the application of pressure in order to flex a portion of the closure and thereby make the opening thereof more difficult for children, none of these closures have provided a viable safety closure due primarily to the ease with which a child can open the safety closure to gain access to the contents of the container. That is, for instance, while depressing the top of the closure in the prescribed manner of opening the closures of these patents, the closures can be pried off the container either by the use of a sharp object or by the use of teeth to grip or bite the closure.

The safety closure of the present invention constitutes an improvement over the closure disclosed in U.S. Pat. No. 3,484,016 in that the closure of this patent has the disadvantages of being subject to being pried open by means of a sharp object, and of being opened by means of gripping or biting the top member with the teeth particularly in the area adjacent the protruding curved part of the bottom member around which the skirt of the top member extends. Another disadvantage of the closure of this patent is that containers utilizing the closures cannot be safely stacked upon each other due to the possibility of accidental opening caused by pressure on the top member.

The provision of stacking strength for the closure while not materially increasing the pressure required to open the closure presents a problem that must be solved in order to provide a viable safety closure. Until the present, however, this problem has not been adequately overcome; and, accordingly, prior art safety closures are deficient in this respect.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to construct a safety closure for a container that cannot be easily opened by children, that has sufficient strength to permit stacking of containers thereon, and that does not require undue force for opening.

The present invention is generally characterized in a safety closure for a container comprising a base member having an upstanding spout, a shoulder extending outwardly from the spout and a ridge protruding from the shoulder, and a cover member having a crown, a skirt depending from the crown and a peripheral bottom edge for the skirt, the cover member being disposed on the base member with the ridge capturing the peripheral bottom edge of the skirt.

Another object of the present invention is to utilize a ridge extending around a base member to capture the peripheral edge of a flexible cover member in order to prevent access to the peripheral edge of the cover member by teeth or sharp objects.

A further object of the present invention is to interconnect a cover member and a base member of a safety closure with a hinge having a weakened portion of reduced cross section such that the hinge will break if an attempt is made to utilize the hinge as a means of opening the safety closure.

The present invention has another object in the provision of a safety closure having an interface between a cover member that is substantially inaccessible to teeth or a sharp object.

Another object of the present invention is the use of discontinuous rings or protrusions to provide stacking strength without unduly increasing rigidity.

A further object of the present invention is to align the protrusions from outer and inner surfaces of a crown of a cover member of a safety closure in order to prevent cantilevered loads and the existence of bending moments.

The present invention has another object in that the skirt and crown of a cover member of a safety closure have a smooth rounded or curved configuration to render gripping thereof difficult.

Yet a further object of the present invention is to reduce the gap between the outer edges of a cover member and the peripheral rim of a base member of the safety closure to a minimum.

Another object of the present invention is to utilize a resilient hinge to interconnect a base member and a cover member of a safety closure to tether the cover member to the base member and resiliently urge the cover member away from the base member to facilitate opening thereof.

Some of the advantages of the present invention over the prior art are that the safety closure of the present invention cannot practically be opened with the use of teeth or a sharp object, that the safety closure has substantial stacking strength without requiring undue force for opening, and that the cover member of the safety closure is tethered to the base member by a hinge without providing a means for opening the safety closure.

Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiment taken in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a cross section of a safety closure according to the present invention in a closed state.

FIG. 2 is a cross section of the safety closure of FIG. 1 during opening.

FIG. 3 is a cross section of the safety closure of FIG. 1 in an open state.

FIG. 4 is a top plan view of the safety closure of FIG. 1.

FIG. 5 is a top plan view of the safety closure in the open state of FIG. 3.

FIG. 6 is a broken side elevation of stacked containers utilizing the safety closure of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As illustrated in FIGS. 1 through 5, the safety closure of the present invention includes a base member 10, a cover member 12 and a hinge 14 interconnecting the base member and the cover member. Base member 10 is adapted to engage the mouth of a container; however, base member 10 can be integrally formed at the mouth of a container provided the configuration of the base member permits the required engagement with the cover member 12 to inhibit opening of the safety closure other than in the prescribed manner.

Base member 10 has a cylindrical neck 16 with a frustro-conical inner surface in order to facilitate dispensing of the container contents. Neck 16 has a beveled bottom edge 18 which extends outwardly to define with an annular flange 20, an annular recess 22 which is adapted to receive the mouth of a container, as illustrated in FIG. 6. The beveled configuration of edge 18 permits easy insertion of the base member 10 into the container in that the diameter of the pointed bottom of edge 18 is less than the diameter of the mouth of the container such that pressure applied to the base member 10 will permit the neck 16 to snap into the container with the edge of the mouth engaged within recess 22.

Neck 16 terminates at an annular shoulder 24 which extends substantially transversely thereto and has an annular ridge 26 protruding therefrom around the outer perimeter thereof. Ridge 26 has an inner surface 28 extending upwardly and slightly inward such that the angle between inner surface 28 and shoulder 24 is less than a right angle, and the outer surface 29 of ridge 26 is smoothly round or arcuate such that the neck 16 joins with the outer surface 29 in a substantially tangential relationship. Shoulder 24 terminates at the top surface of a spout 30 which has a side wall 32 extending upwardly and outwardly at an angle of approximately 65.degree. from shoulder 24. Side wall 32 is rounded to an outer peripheral rim 33 to join an annular top surface 34 of the spout which top surface slopes slightly downwardly at an angle of about 7.degree. to a centrally disposed bore 36 which communicates with the hollow area defined by neck 16. A detachable diaphragm 38 is attached within bore 36, and a leg 40 extends upwardly from diaphragm 38 and has a length sufficient to protrude from the spout 30.

Cover member 12 has a domed crown 42 with three equally spaced stacking protrusions or bosses 44, 46 and 48 extending upwardly from the outer surface thereof at positions offset from the center. The bosses 44, 46 and 48 are relatively thick and extend above the upper-most portion of crown 42 such that when a container is stacked on the safety closure the bottom of the container will not engage the crown. A segmented ring 50 extends from the inner surface of crown 42 in alignment with bosses 44, 46 and 48, and ring 50 has a diameter so as to engage top surface 34 of spout 30. Cover member 12 has an annular skirt 52 depending from crown 42 and the outer surface of skirt 52 terminates at the pointed bottom edge 54 while the inner surface of the skirt has an arcuate configuration to define a gripping edge 56 and a weakened area or flexing portion of reduced cross-section 58. Bottom edge 54 and gripping edge 56 are interconnected by a conical surface 60 to form a bottom peripheral edge for skirt 52. Concentrically disposed within segmented ring 50 is an annular recess 62 which defines a central portion for the crown 42. While cover member 12 has been described as having a crown 42 and a skirt 52 depending therefrom, it will be appreciated that the crown and skirt are integrally formed with a smoothly rounded configuration, such as a portion of the outer surface of a sphere.

Hinge 14 includes a strip 64 attached to base member 10 adjacent ridge 26 and having a rectangular cross-section. Strip 64 is angularly widened at 66 and has a recess 68 therein to define a weakened portion 70 of reduced cross section attached to and contiguous with cover member 12.

The base member 10, cover member 12, and hinge 14 are preferably integrally formed of a flexible, resilient, plastic material such as polyethylene. The walls of base member 10 are relatively thick and rigid; however, hinge 14, crown 42 and flexing portion 58 are relatively thin to permit flexing thereof as will be appreciated from the following description of the use of the safety closure.

The safety closure is illustrated in a closed state in FIG. 1 with cover member 12 disposed on base member 10 such that ring 50 abuts top surface 34 of spout 30 and the bottom peripheral edge of skirt 52 is captured by ridge 26. That is, edge 54 of the skirt abuts ridge 26, and the bottom peripheral edge has a thickness such that gripping edge 56 engages the side wall 32 of spout 30. Flexing portion 58 is positioned so as to surround the outer peripheral rim 33 of spout 30, and hinge 14 is doubled upon itself to resiliently urge cover member 12 away from base member 10.

With the safety closure in the closed state, the capturing of the bottom peripheral edge of skirt 52 by ridge 26 renders the interface of the edge with the base member inaccessible to sharp objects or teeth thereby preventing the cover member from being pried off the base member, and the smoothly rounded configuration of the cover member renders gripping thereof extremely difficult, even with teeth or by biting. Since the bottom peripheral edge of the skirt 52 has a thickness to engage both the ridge 26 and the side wall 32 of the spout, even if the cover member could be gripped, it could not be collapsed by an external force. If an attempt is made to use hinge 14 to remove the cover member from the base member either by prying or by pulling on the hinge, weakened portion 58 will break; and, since weakened portion 58 is contiguous with cover member 10, there will no protrusion remaining which could be utilized to lift the cover member from the base member. Thus, hinge 14 provides the function of capturing or tethering cover member 12 to base member 10 without providing any means for opening the safety closure in other than the prescribed manner.

In order to open the safety closure the central portion of crown 42 defined by recess 62 is depressed such as by use of the thumb, and this depression or flexing of the crown causes a flexing of skirt 52 about a fulcrum provided by abutment of segmented ring 50 with the top surface 34 of spout 30 as illustrated in FIG. 2. The flexing of skirt 52 releases or frees the bottom peripheral edge of the skirt from ridge 26; and, thus, the cover member 12 is free to move away from base member 10. Once the cover member has been depressed, as illustrated in FIG. 2, the cover member moves away from the base member due to the resilient urging of hinge 14 to expose leg 40 and diaphragm 38, and the diaphragm may be removed from the closure by applying an upward force on leg 40 to permit dispensing of the contents of the container. The cover member 12 is tethered to the base member 10, as illustrated in FIGS. 3 and 5; and, in order to return the safety closure to the closed state, the cover member 12 is merely placed over the spout 30 and snapped into place by pressure around the outer edges thereof.

As illustrated in FIG. 6, when a container is stacked on another container utilizing the safety closure of the present invention, the bottom of the upper container engages the upper surface of bosses 44, 46 and 48 and will be spaced from the upper portion of crown 42 to thereby prevent the application of pressure thereto. Bosses 44, 46 and 48 effectively form a discontinuous ring, and the spacing therebetween is sufficient to accommodate a thumb nail during opening of the safety closure by depression of the crown 42.

Segmented ring 50 similarly effectively defines a discontinuous ring formed of a plurality of discrete rib or protrusion segments, and the stacking bosses are aligned with the segments of ring 50 as illustrated in FIGS. 1 and 3 so as to provide thickened portions for the cover member having substantial stacking strength while preventing cantilevered loads and bending moments. The spacing between the protrusions of ring 50 and between the stacking bosses decreases the rigidity of the cover member in order to decrease the force required to depress the cover member such that stacking strength is provided while maintaining flexibility.

The 7.degree. slope of the top surface 34 of the spout permits the configuration of the cover member to be shallow and difficult to grip in that the relation between outer peripheral rim 33, the slope of top surface 34 and the angle of side wall 32 reduce the gap between ring 50 and peripheral rim 33 to a minimum to thereby prevent any gripping force from being applied to this area of the cover member so as to flex the bottom peripheral edge of the skirt and free the cover member.

From the above it will be appreciated that the present invention provides a safety closure which is extremely difficult to open other than in the prescribed manner, and more particularly, cannot be opened by means of sharp objects or teeth to thereby prevent the opening of the safety closure by children. A test of the safety closure of the present invention under proposed formal FDA protocol provided the results that only 1 percent of children not having the benefit of a prior demonstration were able to open the safety closure and, after having the benefit of a demonstration, only 6 percent of the children were able to open the safety closure. Thus, it can be seen that the safety closure of the present invention provides an effective means to prevent access to containers by children while also providing the advantages of stacking strength, a tethered cover member and inexpensive integral manufacture.

Inasmuch as the present invention is subject to many variations, modifications and changes in detail, it is intended that all matter above described or shown in the drawing be interpreted as illustrative and not in a limiting sense.

Claims

What is claimed is:

1. A safety closure for a container comprising a base member having an upstanding spout with annular abutment means disposed therearound; and

a cover member made of flexible material and having a crown, a skirt depending from said crown, a peripheral bottom edge for said skirt, fulcrum means extending internally from said crown and stacking protrusion means extending externally from said crown in alignment with said fulcrum means;

said cover member being disposed on said base member with said peripheral bottom edge of said skirt engaging said annular abutment means and said fulcrum means engaging said spout, said cover member being removable from said base member by depressing said crown to disengage said peripheral bottom edge of said skirt; wherein said fulcrum means includes a ring of discrete segments protruding from the inner surface of said crown and said stacking protrusion means including a plurality of spaced bosses extending from the outer surface of said crown and aligned with said ring of discrete segments.

2. The safety closure as recited in claim 1 wherein said inner surface of said crown has an annular recess therein concentric with and inside said ring.

3. A safety closure for a container comprising a base member having a neck and an upstanding spout, a shoulder extending outwardly from said spout, and a ridge protruding from said shoulder having an inner and an outer surface, said inner surface extending upwardly and inwardly such that the angle between the inner surface and the shoulder is less than a right angle, said outer surface of said ridge being smoothly round or arcuate such that the neck joins with the outer surface in a substantially tangential relationship; and a cover member having a crown, a skirt depending from said crown and a peripheral bottom edge for said skirt, said cover member being disposed on said base member with said ridge capturing said peripheral bottom edge of said skirt whereby said cover member can be removed from said base member by depressing said crown to free said peripheral bottom edge of said skirt.

4. The safety closure as recited in claim 3 wherein said cover member is integrally formed of flexible material.

5. The safety closure as recited in claim 4 wherein said spout has an annular outer top surface, and said cover member has fulcrum means extending internally therefrom to engage said top surface of said spout and provide a fulcrum for freeing said peripheral bottom edge of said skirt when said crown is depressed.

6. The safety closure as recited in claim 5 wherein said spout has a central bore therein extending through said top surface and said top surface has an outer peripheral rim and slopes inwardly from said outer peripheral rim to said central bore.

7. The safety closure as recited in claim 5 wherein said crown is domed and has an inner surface and an outer surface, said fulcrum means includes a ring protruding from said inner surface, and said cover member includes stacking protrusion means extending outwardly from said outer surface of said crown in alignment with said ring.

8. The safety closure as recited in claim 7 wherein said ring is formed of a plurality of discrete segments and said stacking protrusion means includes a plurality of spaced bosses aligned with said ring segments to provide areas of substantial thickness.

9. The safety closure as recited in claim 8 wherein said inner surface of said crown has an annular recess therein concentric with and inside said ring.

10. The safety closure as recited in claim 9 wherein said top surface of said spout has an outer peripheral rim, said shoulder of said base member extends inwardly of said outer peripheral rim of said top surface of said spout, and said spout includes a side wall extending outwardly from said shoulder to said outer peripheral rim.

11. The safety closure as recited in claim 10 wherein said crown and said skirt of said cover member integrally have a smoothly rounded configuration.

12. The safety closure as recited in claim 11 wherein said peripheral bottom edge of said skirt has a thickness to abut said side wall of said spout and said ridge, and said skirt has a flexing portion adjacent said peripheral bottom edge having a thickness less than the thickness of said peripheral bottom edge, said flexing portion surrounding said outer peripheral rim of said top surface of said spout.

13. The safety closure as recited in claim 12 and further comprising a hinge interconnecting said base member and said cover member, said hinge having a weakened portion of reduced cross section whereby said hinge will break if utilized to remove said cover member from said base member without depressing said crown.

14. The safety closure as recited in claim 13 wherein said base member, said cover member and said hinge are integrally formed of flexible, resilient material, and said hinge is doubled upon itself to resiliently urge said cover member away from said base member whereby said cover member is moved away from said base member when said crown is depressed.