Abstract:
A child proof and tamper evident container (C) includes a pail ( 10 ) and a screw top cover ( 12 ) screwed onto the top of the pail to enclose contents of the pail. A latching mechanism ( 18 ) is formed on the pail. A plurality of tamper evident tabs ( 26 ) and second a child proof tab ( 14 ) are formed on the cover. Both types of tabs means engage the latching mechanism as the cover is screwed onto the pail,. The one tab provides an indication as to whether or not the contents of the container have been tampered with, and the second tab prevents a child from removing the cover and opening the container.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This invention relates to the provisional application assigned serial No. 60/338,762 which was filed on Nov. 5, 2001. 
     
    
     
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0002]    N/A  
         BACKGROUND OF THE INVENTION  
         [0003]    This invention generally relates to plastic containers and covers therefore; and more particularly, to a container and cover having a plurality of tabs which make the container and cover both child resistant and tamper evident.  
           [0004]    Containers have long been provided with childproof features that make it difficult, if not impossible, for a child to open a container. In one prior art construction, a screw top cover for a pail includes a tab having an integral projection forming part of the skirt of the cover. Four triangular shaped, raised projections are formed at equally spaced intervals around the rim of the pail. As the cover is screwed down onto the top of the pail, the tab is pressed inwardly for the projection formed by the tab to slide behind one of the four projections formed on the pail. The design of the cover is such that when completely screwed down, the projection formed by the tab on the cover stops slightly beyond one of the projections formed on the pail. The cover tab now springs back so it has a vertical edge abutting the edge of the adjacent projection formed on the top of the pail. This prevents the cover from now being unscrewed unless the tab on the cover is depressed inwardly as the cover is rotated off the top of the pail. Such an operation is readily easy for adults to understand and perform, but not children. The above described construction, however, has drawbacks. The clearance between the tab on the cover and projection on the pail, when the cover is screwed down, is important. If the tab extends too far past a projection, it means the threads on the cover and pail are not properly engaged and leakage may occur. If the tab does not extend far enough, the threads may be too tight. In this circumstance, the cover may not properly close allowing a child to open it. Since many plastic containers are filled with hazardous materials, the potential for danger is increased.  
           [0005]    Besides child resistance, containers have also been provided with tamper evident features that make evident if the container has been previously opened. Tamper evident features can, for example, prevent the addition of foreign substances to the container&#39;s normal contents. It has been reported, for example, that someone will steal an expensive item such as a watch by placing it in a container holding a relatively cheap, bulk material such as pool chemicals. At the check out counter, the thief pays only for the cheap bulk material. More seriously, people have been known to add various types of contaminants to a container. The contaminant can then cause serious injury, or death, if unknowingly mixed with other chemicals, or if a person ingests, or is exposed to the contaminant.  
           [0006]    There have been other approaches to providing tamper evident and child proof containers. U.S. Pat. No. 4,930,656, for example, teaches a removable tear strip for a plastic cover. The strip seals the cover to the top of a container prior to its sale. The customer then tears off the strip before opening the container. U.S. Pat. No. 5,310,074 teaches a screw top container having a hidden locking mechanism that prevents children from removing the top. However, there is no provision for indicating if there has been tampering with the container. U.S. Pat. No. 5,915,575 teaches a screw top container having a locking mechanism incorporated into a cover for the container. The mechanism includes a lever pivotable about a vertical axis. While the mechanism makes it difficult for children to open the container, there is nothing to indicate if tampering has occurred. Finally, U.S. Pat. No. 6,006,942 is for a container with a locking mechanism having a lever pivotable about a horizontal axis. While resistant, there is again no provision of something to indicate tampering.  
         BRIEF SUMMARY OF THE INVENTION  
         [0007]    The present invention is directed to an improved container having both child proofing features and tamper evident features. The container includes a pail having a threaded opening at its upper end and a screw top cover correspondingly threaded for the cover to be screwed onto the top of the pail and enclose contents of the pail. A latching mechanism formed on the pail includes a plurality of triangular shaped tabs located at spaced intervals around the periphery of the top of the pail. First and second tabs are formed on the cover both tabs engaging the latching mechanism as the cover is screwed onto the pail. The first tab provides an indication as to whether or not the contents of the container have been tampered with. The second tab prevents a child from removing the cover and opening the container.  
           [0008]    In a preferred embodiment of the invention, there is at least one of the first tabs formed on the cover for providing an indication of tampering. To remove the cover from the container requires the end user to depress both tabs at the same time. Because of the size of the cover, and spacing of the tabs, this is physically impossible for most people to do. Rather, to remove the cover, the person will tear off the tab or tabs. However, absence of the tabs is readily apparent and provides an immediate indication of tampering prior to a sale or use of the container. Since the containers are typically sold in retail establishments, containers which have been tampered with are readily identified while still in inventory, or at the point of sale. Containers which have been tampered with can thus be removed before anyone is harmed. After the sale, prior to the first use, the tamper evident tabs are removed. However, the other tab, which prevents a child from opening the container remains in place so children cannot open the container.  
           [0009]    Other objects and features will be in part apparent and in part pointed out hereinafter. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0010]    The objects of the invention are achieved as set forth in the illustrative embodiments shown in the drawings which form a part of the specification.  
         [0011]    [0011]FIG. 1 is a top plan view of a tamper evident container and screw top cover of the present invention;  
         [0012]    [0012]FIG. 2 is a top plan view of the container with the cover removed;  
         [0013]    [0013]FIG. 3 is an elevation view, partly in section, of the container and its cover;  
         [0014]    [0014]FIGS. 4 a - 4   c  are a series of plan views sequentially illustrating how the cover is screwed onto the top of the container, FIG. 4 d  illustrates how the cover must be moved in the opposite direction to open the cover, and FIG. 4 e  illustrates how a tamper evident tab of the cover is locked in place;  
         [0015]    [0015]FIG. 5 is an elevation view of a child resistant cover tab; and,  
         [0016]    [0016]FIG. 6 a  is a partial elevation of the cover with the tamper evident tab, and FIG. 6 b  is a sectional view of the cover and pail with the tamper evident tab in place.  
     
    
       [0017]    Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.  
       DETAILED DESCRIPTION OF INVENTION  
       [0018]    The following detailed description illustrates the invention by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what I presently believe is the best mode of carrying out the invention. As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.  
         [0019]    Referring to the drawings, in FIG. 1, a tamper evident and child proof container C of the present invention is shown to include a screw top pail  10  having an integrally formed bail  11 , and a separate locking cover  12 . Container C typically includes chemicals or powdered material which can harm a child. Also, the contents of the container may be such that if unauthorized persons have access to the contents, it is important that this be immediately known. In accordance with the present invention, both situations are addressed by the design and construction of the pail and its cover.  
         [0020]    Pail  10  and cover  12  are both made of a molded plastic material. The open, top end of pail  10  is threaded about its outer surface as indicated at T 1 . Cover  12  is correspondingly threaded as indicated at T 2  so the cover can be conveniently used to close and seal the container. A child proof feature of the container is provided by a tab  14  integrally formed with cover  12  as part of a skirt  16  of the cover. Child proofing and tamper proofing is further facilitated by a latching means which includes a plurality of triangular shaped locking tabs  18  which, as shown in FIG. 2 are equally spaced around a rim  20  of pail  10 . Each tab  18  projects inwardly from the outer edge of rim  20  across a channel  21  formed in the top of the pail though which the threaded portion of cover  12  rotates when the cover is screwed down onto the pail. While four tabs  18  are shown in FIG. 2, those skilled in the art will recognize that other numbers of tabs can be used without departing from the scope of the invention.  
         [0021]    As shown in FIGS. 4 a - 4   c , tab  14  has a flange F extending outwardly from the base of the tab. When container C is to be closed, cover  12  is placed down over the top of pail  10  and turned or rotated until the cover is screwed tightly down over the pail. As cover  12  is screwed down, a leading edge  22  of a flange F contacts one of the tabs  18 . As shown in FIGS. 4 a - 4   e , the pail tab is of a triangular configuration having an angled leading edge  18   a , and a straight trailing edge  18   b . Rotation of cover  12  to screw it onto the top of pail  10  is from right to left as viewed in FIGS. 4 a - 4   e . When leading edge  22  of flange F contacts edge  18   a  of tab  18  as shown in FIG. 4 a , tab  14  is forced inwardly as the cover continues to be turned. Leading edge  22  of the tab is an angled surface which promotes inward deflection of tab  14 . In addition, as shown in FIG. 5, a recess W extends across the top of tab  14  forming a line of weakness which acts as a flex point for the tab.  
         [0022]    In FIG. 4 b , tab  14  is shown being flexed so that the backside of the tab presses against a rib R extending outwardly from the side of pail  10 . The rib limits the extent to which tab  14  is pressed inwardly. At this point, leading edge  22  of tab  14  changes to a flat spot  23  which rides over the tip of tab  18  as tab  14  slides past tab  18 . Immediately past surface  23  of the flange a recess N is formed in the flange. As shown in FIG. 4 c , when flat spot  23  moves past the tip of tab  18 , tab  14  flexes outwardly away from rib R with tab  18  now being captured in recess N. Recess N provides a {fraction (1/32)}″-{fraction (3/16)}″ spacing for the tab. This allows the user to continue turning cover  12  so he or she is sure tab  14  has been moved past tab  18 .  
         [0023]    Once the cover is in place, it can be removed by turning it in the opposite direction, while at the same time pressing tab  14  inwardly so tab  18  is clear of recess N. This is as shown in FIG. 4 d . Otherwise, one must try to force the flange portion of tab  14  past locking tab  18 . Small children typically lack the understanding and/or dexterity to depress tab  14  inwardly while rotating cover  12 . They also do not have enough strength to force flange F past tab  18 . Neither do adults. Accordingly, tab  14  renders the container child proof as well as tamper resistant.  
         [0024]    Importantly, the present invention also utilizes the combination of child resistant cover tab  14  and the pail tab  18  to make container C tamper resistant, but further includes a tamper evident cover tab  26  for this purpose. This aspect of the present invention is accomplished by having at least one, and preferably two or more of tamper evident tabs  26  spaced about cover skirt  16 . As with tab  14 , the tamper evident tabs  26  are integrally formed with cover  12  as part of skirt  16 . In FIGS. 6 a  and  6   b , tamper evident cover tab  26  is shown to be generally identical to child resistant cover tab  14 . As such, tab  26  has a flange F′ extending outwardly from the base of the tab. Flange F′ includes a tapered leading edge  22 ′ with a flat spot  23 ′ immediately behind it. However, recess N′ comprises a notch formed between flat spot  23 ′ and an outwardly extending section  24  formed immediately behind the recess. Locking in place of tab  26  is shown in FIG. 4 e . In addition, as shown in FIG. 6, a recess W′ extends across the top of tab  26 . Besides forming a line of weakness which acts as a flex point for the tab when cover  12  is being installed on pail  11 , the recess further provides a membrane for tearing the tabs  26  off of cover  12 , as described hereinafter. Also, on the tamper evident tab or tabs only, the depth of the tab is greater than the gap between the pail tab  18  and pail rib R. The tamper evident cover tabs  26  make container C tamper resistant because it is physically difficult or impossible for one person to depress three or more cover tabs (i.e. one child resistant cover tab  14  and two or more tamper evident cover tabs  26 ) while simultaneously rotating the cover  12  in the direction to remove the cover. Coupled with this is the tab depth which, as noted above, is greater than the gap in the pail. This makes it very difficult to turn the cover back in the reverse direction, even by two people, and even if only one tamper evident tab is present. It will be understood by those skilled in the art that the torque required for initial installation of the cover is greater than would otherwise be expected, but the cover is installed at the factory using automated equipment, this is not a problem for the consumer. Opening container C, with these tamper evident features, might be accomplished by a person with large hands who can hold pail  10  between his or her legs to keep the pail from rotating with the cover while attempting to remove the cover. Removal of the cover might also be accomplished by two people acting in concert. In the store environment, however, either action would be somewhat obvious and suspicious. Additional protection from circumvention of the tamper evident and tamper resistant features of the invention is provided by a section  24 . This section prevents the tamper evident tabs from being manipulated (pulled and/or twisted) through the gap in the pail. It will be understood by those skilled in the art that the height, width, and depth of this section are important design considerations in making the invention work.  
         [0025]    Once container  10  has been purchased (unopened and with the correct contents), the consumer will want to open it. This is accomplished by first tearing off all of the tamper evident cover tabs  26  from cover  12 . Then, pail  10  and cover  12  combination will be left with only the child resistant feature of the present invention provided by child resistant cover tab  14 . An adult can then easily remove the cover as previously described and shown in FIG. 4 d . However, a child does not have either the knowledge or strength to simultaneously press in on tab  14  to disengage it from its associated locking tab  18 , while turning cover  12 .  
         [0026]    Each tamper evident cover tab  26  is connected to cover  12  by the thin membrane provided by the recess W′. Depending on the thickness of the recess, the tamper evident cover tabs  26  can be made to be more or less easily torn from the cover  12  so that a hand tool, such as a pliers, might be required. If any of the tamper evident cover tabs  26  has been removed from cover  12 , it is evidence an attempt was made to open container C. The fact the tamper evident cover tabs  26  must be removed in order to open the container provides the evidence of tampering.  
         [0027]    In one embodiment of the invention, cover  12  is made of a resilient material such as an injection molded plastic. The cover threads are molded integrally with the rest of the cover in a mold having a rotating core or cavity, all as is known to one of ordinary skill in the art. Child resistant cover tab  14  is formed using conventional slides in the cavity to provide vertical separation between the leading and trailing edges of the tab and cover skirt  16 . Tamper evident cover tabs  26  are constructed using slides. Pail  10  is molded including slides which to strengthening ribs R as well as forming the tabs  18 .  
         [0028]    In view of the above, it will be seen that the several objects and advantages of the present invention have been achieved and other advantageous results have been obtained.