Abstract:
The present invention is directed to an improved container closure or lever cap comprising one or more of the following features: (i) an improved interface on the interior surface of the closure that consists of strategically positioned locking lugs to securely affix the closure onto a container, (ii) a repositioned lever handle and fulcrum to optimize function and mechanical advantage, (iii) a retro-fit sleeve for an incompatible container, which on the inner surface is fashioned to interface with twist necks bottles, or other closure designs and mechanisms incompatible with the interior fitting of the lever cap, and which on the exterior is fashioned to receive the interior fitting of the lever cap, (iv) a tamper-evident safety indicator, (v) a specialized vertical sloping sidewall at the container&#39;s distal end near the opening to improve the closure&#39;s vertical lift during operation, (vi) a child safety design and mechanism that requires two functions to unlock the lever and position it for normal operation, and (vii) certain ergonomic, aesthetic, and customizable features that improve its function and consumer appeal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims priority from U.S. patent application Ser. No. 09/579,050, filed on May 26, 2000, now U.S. Pat. No. 6,860,397 which was based on U.S. Provisional Patent Application No. 60/136,332, filed on May 26, 1999. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is directed to an improved container closure, and, in particular, a lever cap. 
   2. Description of the Related Art 
   Although the term “bottle” is often used in this patent and in the prior U.S. patent application Ser. No. 09/579,050, any container is intended, and may include, without limitation, bottles, jars, canisters, pill and medicine bottles, jugs, cans, drums, and all other containers of various shapes, sizes, and capacities on which the present invention may be used, provided such container&#39;s opening can be produced, fashioned, or retro-fitted to received the lever cap; use of the word “container” or any other vessel mentioned above shall be deemed to incorporate all such terms. Furthermore, the present invention may also be referred to herein by the use of different terms, including, “closure”, “container closure”, “cap”, “lever cap”, “covering”, or “lid”. 
   BACKGROUND TO THE INVENTION 
   Container closures, such as the early bottle crown caps, typically consisted of a circular piece of die stamped steel or other suitable metal that was crimped over the top lip or bead of a bottle. This device provided a secure and reliable closure, but required a tool to remove it. Typically, the cap was removed with an opener that would engage a portion of the lower edge of the bottle cap, and with sufficient force, outwardly deform a portion of the metal crimps causing the cap to be lifted upward and removed. This movement had the effect of distorting the original crimping structure at the bottom edge of the cap, and often permanently creased the top of the cap into a shape that prevented it from being effectively reused. 
   Removing a crown cap from a bottle also required two hands, one to hold the bottle and the other to manipulate the opener. In certain circumstances such as commercial applications, the bottle opener was often permanently affixed to a wall or the dispensing machine, thereby permitting the use of only one hand, but still, such a tool was needed. Over the years numerous patents were filed on various bottle opening tools. One common feature of nearly all of these bottle cap removers was the similarity in which they operated. Whether they employed a single handle with a hooked edge for engaging the bottom of the bottle cap, or a more elaborate structure, each bottle cap remover was a separate device that was brought in contact with the cap to pry the cap off in an outward and upward direction. Once the cap was removed, it was usually deformed and unsuitable for reuse and had to be discarded. 
   A more recent improvement to the crown cap was the twist off bottle cap, which is commonly used for soda bottles and other containers that require a secure seal to prevent the container&#39;s pressurized contents from escaping. This cap has an interior threaded structure compatible with the bottle&#39;s exterior threaded structure near the bottle&#39;s opening. The twist off cap is designed to be reusable and provides a tight seal to secure the contents within the container. Although it does not require a separate tool to remove it, in practice, it is often quite difficult to initially release, because it is tightly affixed to the bottle, requires two hands, and necessitates a strong twisting motion of the wrists and arms to both remove and securely replace it. A significant amount of grip-strength is also required to hold the cap while twisting it with sufficient torque to overcome the tight seal and break the connecting tabs that attach the cap to the separable tamper-evident safety ring that remains on the bottle after the cap is removed. This retained ring, which until the bottle is opened is attached to the removable cap, acts as a visible tamper-evident safety seal. These caps typically exhibit vertical ridges or other raised textures on their exterior to improve grip contact and minimize hand slippage, but they are usually shallow and often inadequate. The force required to initially twist the cap is sometimes so great that a separate tool is often employed to increase the user&#39;s mechanical advantage, overcome the friction and tension of the cap&#39;s tight seal on the bottle, break the safety tabs connecting the retained ring to the cap, and then remove the cap from the bottle. 
   Although both of these closures mentioned above have the ability to securely seal a particulate, fluid, or pressurized gas within the container, both are often difficult to remove and, except for rare circumstances, require two strong hands. Other closure technologies have been developed in recent years, such as flip-tops, pull-tops, toggle, and twist-spout caps, but none have the strength and sealable ability to hold a pressurized beverage contents, such as sparkling water, soda, or beer, securely within the container. Most of these closures are fine for water and other non-pressurized liquids, but for this reason pressurized beverages continue to be sold only with crown or twist caps. Although jars have often used large twist off tops and press-fit lids requiring a tool to remove, both of these closures are variations of those discussed above. 
   The market is ready for a simple, easy open closure that requires no tools, can be operated with one hand, and is capable of securely holding both pressurized and non-pressurized contents. Consumers, especially the increasing elderly population, young children, and others with compromised abilities, would readily embrace this technology, and see it as an improvement in customer-focused, ergonomic packaging design. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to, in the first aspect, an improved container closure comprising: an improved internal cap closure mechanism consisting of strategically positioned locking lugs, which are designed to work in communication with a container&#39;s locking lip to securely attach such closure over the container&#39;s orifice. 
   In another aspect, the present invention is directed to an improved container closure comprising: an improved handle and fulcrum that is positioned to optimize function and mechanical advantage, wherein the handle over the fulcrum acts as a lever when squeezed against the sidewall of the container near the container&#39;s distal orifice to provide sufficient stretch and lift to remove the closure from the container. 
   In yet another aspect, the present invention is directed to an improved closure and container system comprising: a retro-fit sleeve that would enable the lever cap to be used with twist off bottles and other containers that currently can not communicate with the lever cap&#39;s inner locking mechanism, where the sleeve is fashioned to have an inner configuration capable of interfacing with such twist off bottles and other containers, and an exterior that is fitted to receive the lever cap, which would allow a wide variety of containers with dissimilar closure systems to be retro-fitted to use the lever cap. 
   In yet another aspect, the present invention is directed to an improved container closure comprising: a tamper-evident safety feature to indicate if the lever cap has been previously removed, and would deform and/or discolor the first time the handle is depressed against the sidewall of the container. 
   In yet another aspect, the present invention is directed to an improved closure and container system comprising: a specialized vertical sloping sidewall on the container near the container&#39;s distal orifice to improve the closure&#39;s stretch and vertical lift during operation. 
   In yet another aspect, the present invention is directed to an improved closure and container system comprising: a specialized child safety design and mechanism that provides a lever retention locking bar and locking thumb gate, which requires one function to lock the lever for safety and two functions to unlock and position it for normal operation. 
   In yet another aspect, the present invention is directed to an improved closure and container system comprising: certain ergonomic, aesthetic, and customizable features that improve its function, such as molded or insertable gaskets, and enhance consumer appeal, such as a unique finger ring design for holding and manipulating the handle and cap. 
   The closure may comprise one or more of the following features: (i) an improved interface on the interior surface of the closure that consists of strategically positioned locking lugs, instead of a full locking ring, to securely affix the closure onto a container, (ii) a repositioned lever handle and fulcrum to optimize function and mechanical advantage, (iii) a retro-fit sleeve for an incompatible container, which on the inner surface is fashioned to interface with twist necks bottles, or other closure designs and mechanisms incompatible with the interior fitting of the lever cap, and which on the exterior is fashioned to receive the interior fitting of the lever cap, (iv) a tamper-evident safety indicator, (v) a specialized vertical sloping sidewall at the container&#39;s distal end near the opening to improve the closure&#39;s vertical lift during operation, (vi) a child safety design and mechanism that requires two functions to unlock the lever and position it for normal operation, and (vii) certain ergonomic, aesthetic, and customizable features that improve its function and consumer appeal. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features of the invention believed to be novel and the elements characteristic of the invention are set forth with particularity in the appended claims. The FIGS. are for illustration purposes only and are not drawn to scale. The invention itself, however, both as to organization and method of operation, may best be understood by reference to the description of the preferred embodiment(s) that follows taken in conjunction with the accompanying drawings in that: 
       FIG. 1  is a schematic top/side view of the lever cap showing the internal locking lugs, handle, and the impervious gasket; 
       FIG. 2  is a schematic top view of the cap&#39;s inner locking mechanism and lever handle placement; 
       FIG. 3  is a schematic top/side view of the cap fully engaged on the neck of a bottle with the closure apparatus in the closed or engaged position; 
       FIG. 4  is a schematic top view of the inner portion of the cap showing the locking lugs and the outer perimeter of the bottle&#39;s orifice and locking lip; 
       FIG. 5  is an exploded schematic top/side view of the cap and a bottle ready to receive the cap; 
       FIG. 6  is an exploded schematic top/side view of the cap, the retro-fit sleeve, and a twist on/off fitted bottle; 
       FIG. 7  is a schematic top view of the cap with an embodiment of an internal locking mechanism and lever handle location different from that disclosed in  FIG. 2 ; 
       FIG. 8  is a schematic side view of the container and the cap with the tamper evident safety feature; 
       FIG. 8   a  is a schematic side view of the cap with the tamper evident safety feature and the container with a non-linear sidewall for improved leverage; 
       FIG. 9  is a schematic side view of the container and the cap with the lever handle and cap in the closed or engaged position; 
       FIG. 10  is a schematic side view of the container and the cap with the lever handle and cap in the partially open or partially disengaged position; 
       FIG. 11  is a schematic top/side view of the cap on a container with a safety locking bar and the lever handle in the engaged or locked position; 
       FIG. 12  is a schematic side view of the cap on a container with a safety locking bar and the lever handle in the engaged or locked position; 
       FIG. 13  is a schematic side view of the cap on a container with a safety locking bar and the lever handle in the disengaged or unlocked position; 
       FIG. 14  is a schematic side view of the cap on a container with a safety locking bar and the cap with lever handle twisting from a disengaged or unlocked position to an engaged or locked position; 
       FIG. 15  is a schematic side view of the cap on a container with a depressible thumb gate and non-overlapping safety locking bar with the cap&#39;s lever handle in the engaged or locked position; 
       FIG. 16  is a schematic side view of the cap on a container with a depressible thumb gate and overlapping safety locking bar with the cap&#39;s lever handle in the engaged or locked position; 
       FIG. 17  is a schematic top/side view of the cap with customized ergonomic and aesthetic features; 
       FIG. 17   a  is a schematic top/side view of an alternative cap with customized ergonomic and aesthetic features; and 
       FIG. 18  is an exploded schematic side view of the cap, a separate fluid/gas impervious gasket, and container. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In describing the preferred embodiment of the present invention, reference will be made to  FIGS. 1 through 18  of the drawings in that like numerals refer to like features of the invention. Features of the invention are not necessarily shown to scale in the drawings. 
   Locking Lugs and Handle Placement 
   The lever cap of the present invention is an improved device over prior designs in performance, ease of operation, and cost. The primary mechanical improvement of this closure over the prior case and all prior art involves using carefully positioned locking lugs on the inside of the closure, thereby eliminating the need for an entire bead to engage the container&#39;s lip, and the placement of the lever handle in relation to the locking lugs. As illustrated in  FIG. 1 , lever cap  1  is shown with gasket  2 , the location of the outside edge of the container&#39;s locking lip  3 , specially positioned locking lugs  4 ,  5 , and  6 , and handle  7 . Locking lugs  4 ,  5 , &amp;  6  are an improvement to a solid locking ring on the interior of the cap for a number of reasons, and can comprise coverage as little as one third the circumference of such former solid locking ring. First, the surface area of a solid locking ring as engaged against the container&#39;s locking lip is more that necessary to sealably secure a container&#39;s contents. Second, three appropriately positioned locking lugs provide all of the strength necessary to sealably secure most commercially available contents. Third, this triad of locking lugs presents less surface area and, therefore, provides a significantly easier impediment to overcome during the cap&#39;s removal. 
   Although the locking lugs could be of any number, size, shape, and location around the locking ring area on the underside of the cap, the first preferred design, depicted in  FIGS. 1 ,  2 ,  3 , &amp;  4 , would be three lugs, shaped and generally positioned as shown. Using the face of a clock for reference with the handle of the cap situated in the 6:00 o&#39;clock position, while looking at the underside of the cap, there would be a lug  4  shown and shaped as depicted in  FIGS. 1 ,  2 ,  3 , &amp;  4  at the 9:30 to 11:00 o&#39;clock position. There would be another lug  5  shown and shaped as depicted in  FIGS. 1 ,  2 ,  3 , &amp;  4  at the 1:00 to 2:30 o&#39;clock position. Finally, there would be a third lug  6  shown and shaped as depicted at the 5:30 to 6:30 o&#39;clock position near and opposite the handle. Certainly, different applications with different sized and shaped containers may require more or less locking lugs and handles in different shapes and configurations, but all such embodiments are contemplated herein. For example, and without limiting the foregoing, on a square, rectangular, or triangular shaped container, the locking lugs may be at the corners and more than one handle may be required. Additionally, the plurality of lugs can be substantially equidistantly dispersed about the circumference of the closure. Additionally, the lever cap can utilize other structures and techniques for providing the removable connection to the container, such as, for example, snap-fit, press-fit, friction-fit or other suitable means, or structures. 
   Operationally, the removal action is quite simple, and these improvements disclosed herein provide a simplified opening method. To remove the cap, only the locking lugs need to be separated from the container&#39;s lip. The user would hold the container in one hand and place either the thumb, the middle area of the hand between the thumb and the forefinger, or the pointer and/or middle finger against the lower part of the handle. Gripping the container firmly, the user would then apply a squeezing force against the handle in the direction of the container. As this force is applied, such force would be deflected, in part, off the sidewall of the container and transferred to the container&#39;s closure, thereby forcing at least a portion of the closure to stretch beyond the leading edge of locking lug  6 . As the force continues, and because of the handle&#39;s shape and its angle to the container&#39;s sidewall, it would be expressed in an upward direction, thereby causing the cap to disengage from the lip of the container at locking lugs  4  &amp;  5  to result in the complete release of the closure&#39;s hold on the container. Once the closure&#39;s hold is released, the cap would be easily removed from the container. The closure is reusable and can be replaced over the container&#39;s opening to sealable secure the container&#39;s contents for storage or transport. 
   In this first preferred embodiment, as shown in  FIGS. 1 ,  2 ,  3 , &amp;  4 , the shape of the locking lugs are designed to allow them to not only hold the cap firmly on the container, but to more easily slip over the container&#39;s locking lip when the cap is being removed from the container. The inner most edge of the locking lug  6  would be concaved shaped to closely follow the curvature of the container&#39;s lip. Locking lugs  4  &amp;  5  would be further shaped to allow the leading edge of the locking lug, which would first experience the force of slipping over the container&#39;s lip, to be reduced in size to permit less material to initially pass over the container&#39;s lip. Furthermore, this particular shape would act like a wedge thereby permitting a gradual ramp up to the thicker portion of the locking lugs, which provide the majority of the security in firmly holding the cap onto the container&#39;s lip. The shape and configuration of these locking lugs would ease the process of removing the cap and require less force to be applied than if the cap&#39;s inner locking ring were fully engaged under the container&#39;s lip. Since less force is required to disengage the cap, then handle  7 , depicted in  FIGS. 1 ,  3 , &amp;  8 - 18  could be reduced in size and require less force to be applied against it to release the cap&#39;s hold on the container&#39;s lip. Likewise, since only the locking lugs need to engage the container&#39;s lip, less force will be required when replacing the cap onto the container. Many users, such as children and the elderly, will especially appreciate this ease in opening and resealing the cap. Furthermore, this locking lug structure would also allow the cap to be streamlined and save on the amount and cost of material during manufacture. 
   In a second and more preferred embodiment, depicted in  FIG. 7 , the three locking lugs  4 ,  5 , &amp;  6  would be positioned in similar fashion to the first preferred embodiment, but the handle would be positioned in the area near and opposite the space between locking lugs  4  &amp;  5 . The physical operation from the user&#39;s standpoint would be identical to that disclosed in the first embodiment. This most preferred embodiment would apply the greatest strength to the strongest area first, i.e., the widest part of locking lugs  4  &amp;  5 , resulting in an overall easier removal than that described in the first embodiment. As the force on the handle is applied, it would be deflected, in part, off the sidewall of the container and transferred to the container&#39;s closure, forcing at least a portion of the closure to stretch beyond the leading edges of locking lugs  4  &amp;  5 . Since the force on the handle would reach its highest level during the primary thrust against the container&#39;s sidewall, this effort should be directed to release the most significant points of resistance at the point of maximum mechanical advantage. The inner most edges of the locking lugs  4  &amp;  5  would be concaved shaped and tailored to easily retreat off the curvature of the container&#39;s locking lip. Especially if these leading edges of locking lugs  4  &amp;  5  were rounded, beveled, chamfered, catty-cornered or otherwise presented without a sharp corner, the handle in this location between locking lugs  4  &amp;  5  would address the strongest resistance and most difficult removal points first, which would require the greatest amount of force, but, once passed, the balance of the operation would be significantly easier than that disclosed in the first embodiment since only the hold on the one locking lug  6  remains, rather than on two locking lugs. A continued upward force would easily result in removing the rest of the cap from the container. 
   The cap and appended handle could be formed from any appropriate material, including, without limitation, metal, plastic, fiberglass, or any suitable material or composite of materials by any suitable process, including stamping, molding, injection molding, thermoforming, or other appropriate process. A preferred material for manufacture would be plastic, and the most preferred choice from the polymer group would be a high-density polyethylene or variation, composite, or derivative thereof. Since the cap is intended to be reused numerous times, the selection of material offering optimum strength, stretch, sealability, and aesthetics would be important to its commercial success. Since some of the cap&#39;s intended uses would cause it to come in contact with food, beverages, medicine, and perhaps other products designed for human consumption, such materials for these applications may need to be compliant with the requirements of the U.S. Food and Drug Administration and could also include various additives, chemistries, and other means for antimicrobial protection for the benefit of the user, as well as for the integrity of the cap. Ideally, the cap with appended handle would be injection molded in one piece, but other suitable manufacturing methods could be employed by those skilled in the art, including, without limitation, the manufacture of the cap portion and handle portion separately, with subsequent assembly by adhesive, ultrasonic, heat staking, or other suitable method known to those skilled in the art. Additionally, the handle  7  can have upper and lower portions that are at an angle with respect to each other with the fulcrum portion  22  disposed between the upper and lower portions. 
   The method of use, as shown in exploded  FIG. 5  would be to firmly snap or fit cap  1  onto container  9  and over container opening  10  such that locking lugs  4 ,  5  &amp;  6  would slide over container locking lip  8  with the fulcrum  22  of handle  7  resting on or near the distal portion of container sidewall  11  near container opening  10  and below locking lip  8 .  FIG. 3  depicts cap  1  in the engaged or closed position on container  9 , and  FIG. 5  depicts cap  1  in the disengaged or open position. The method of removal of cap  1  from container  9  would be as described above. 
   Retro-Fit Sleeve 
   The lever cap can only be effectively used on a compatible container. In the event such cap is desired to be used on a container with an incompatible closing mechanism, a retro-fit sleeve or adapter may be used as an acceptable interface to preserve the use of the incompatible container and yet obtain the features and convenience of the lever cap.  FIG. 6  illustrates the concept of the retro-fit sleeve in an exploded view. In this case,  FIG. 6  depicts container  21  fashioned with a standard screw or twist-on closure mechanism, i.e., threads, common to many commercially available beverage containers. Retro-fit sleeve  12  is fashioned with an interior closing mechanism or securing structure  15  that is compatible with exterior closing mechanism or securing structure  16  of container  21 . Of course, the securing structures can be other types that provide for securing of the sleeve to the container, such as, for example, a snap-fit or press-fit device. Retro-fit sleeve  12  is spun or otherwise fitted onto container  21  such that closing mechanisms  15  and  16  communicate to form a tight and impervious seal to liquids, particles, gases, fluids, and other substances, down to container stop ring  19 , if present, which is standard on most beverage containers, such that container opening  10  and retro-fit sleeve opening  20  are flush across such openings at container top edge  17  and retro-fit sleeve top edge  18 . Lever cap  1  would then be fitted onto retro-fit sleeve  12  across the joint openings at container top edge  17  and retro-fit sleeve top edge  18  such that handle  7  at fulcrum  22  rests on or near retro-fit sleeve sidewall  14  below retro-fit sleeve locking ring  13 . The removal and refitting operation of cap  1  would be as described above, as if container  21  was originally fashioned to receive cap  1  without the interface of retro-fit sleeve  12 . 
   Retro-fit sleeve  12  is shown in  FIG. 6  with a vertical sidewall  14 . However, it may also be fashioned with a specially contoured sidewall, including, without limitation, a sloped sidewall such as the one depicted as  25  on container  26  in  FIG. 8  and described below. 
   Preferably, retro-fit sleeve  12  would be manufactured in the same way and from the same materials as described above for the lever cap, but, as determined by one skilled in the art, it may be fashioned in host of different ways and from different materials as may be dictated by each application. 
   Tamper-Evident Safety Indicator 
   If the lever cap is to gain commercial acceptance for substances intended for human consumption or other specialized use where a consumer would want to know if the container had been previously opened, then an integrated tamper-evident safety feature, which would serve as an indicator that the cap had been previously removed, or the seal broken, may be a required or, at least, desired safety feature. Certainly, a cap could be shrink-wrapped for safety, as is common with pharmaceutical products, or a foil-like seal could be affixed across the container&#39;s opening under the cap, as is common with food products, but an integrated feature on the cap itself may have commercial benefit. A tamper-evident safety indicator depicted as  23  on  FIGS. 6 and 24  on  FIG. 8  may be used on lever cap  1  under lever handle  7  regardless of the container used. It may be used on container  9  straight vertical sidewall  11  as shown in  FIG. 5 , on the retro-fit sleeve  12  sidewall  14  as shown in  FIG. 6 , or on a specially contoured sloped sidewall  25  on container  26  as shown in  FIG. 8 , as described below. This type of tamper-evident safety feature would be comprised of a specially designed septum or angle that would deform and/or discolor the first time the handle is depressed against the sidewall of the container or otherwise actuated. These qualities could be effected as a result of the structure of such septum or the composition of the materials used in its construction, such as, for example, due to stress. Many such features are well known to those skilled in the art, and any number of them could be incorporated into the lever cap, all of which are contemplated herein. If desired, other commercially available safety features such as shrink-wrap packaging, and foil, foam, plastic, or paper covers affixed over the opening can be used in conjunction with the tamper-evident safety indicator. Additionally, the tamper evident device could be actuated based upon actuation of the handle and/or removal of the closure from the container and/or sleeve. 
   Sloping Sidewall 
   One of the principal mechanical improvements to the lever cap is its companion interface on the container at the point of the fulcrum&#39;s communication with the container&#39;s sidewall. As shown in  FIGS. 8 ,  8   a ,  9 , &amp;  10 , container  26  is fashioned with a vertical sloping sidewall  25 . Although some bottle and packaging concepts have incorporated this kind of vertical sloping sidewall feature into their container design for a number of years, never before has such feature been used as an integral part of the container&#39;s cap removal process. 
   This sloping sidewall feature is a preferred embodiment to the cap&#39;s smooth, easy, and reliable removal on a regular basis. The principal requirement in removing any cap from a container is to attain vertical lift during the removal process. Applying a force horizontally, such as the force on the lever handle toward the container&#39;s sidewall, has to be translated into a vertical direction to remove the cap. Although workable with purely vertical sidewalls, there is a certain amount of inefficiency in this arrangement. However, if the container&#39;s sidewall could have a vertical sloping inclination off true center, such as that depicted in  FIGS. 8 ,  8   a ,  9  &amp;  10 , then the horizontal force on the lever handle would be more efficiently translated into the vertical force necessary to drive the cap from the top of the container. The slope&#39;s angle of inclination is subject to change depending on the application, the size of the cap, and the minimum force desired to drive the cap vertically. Considering that any variation off a center plumb line would have some measure of benefit to aid in achieving vertical efficiency, all angles between true horizontal and true vertical are possible, and, therefore, contemplated herein, with a technically optimum preferred angle of 45 degrees. Furthermore, a curved slope, as shown by slope  25  in  FIG. 12 , is also contemplated with changing angles of inclination over the distance of the sloping portion, which could assist in the cap&#39;s removal in certain applications. However, depending on the materials used and the desired benefits to be achieved in each situation, each application will dictate the optimum angle or angles of inclination for the slope of the sidewall. 
   As shown in  FIG. 8   a , the slope of the sidewall can also be non-linear, such as, for example, a reverse S-like shape. Such shapes facilitate removal of the closure and improve the leverage of the handle  7 . 
   The fulcrum, which is the point of communication between the container sidewall and the cap&#39;s handle, is important and subject to change in each application. The factors necessary to its successful use, a part of which is maximizing the handle&#39;s force efficiency, would be its size, shape, configuration at the point of contact with the container&#39;s sidewall, the contour of the container&#39;s sidewall, and its coefficient of friction resulting from its design and the materials used in its composition. All of these factors need to be taken into account by one skilled in the art to design the optimal match between the handle&#39;s fulcrum and the container&#39;s sidewall to achieve a point of interface which minimizes the attendant friction and maximizes the strength of the handle and the efficiency of the amount of force required to remove each cap in each application. General guidance would include a shape and point of contact at the bottom of the fulcrum to be as small, smooth, and strong as practicable to reduce the friction between the fulcrum and the container sidewall during operation and the selection of polymeric or other suitable materials that balance strength, rigidity, and the optimal coefficient of friction to achieve a strong, slippery surface at the interface between the fulcrum and the sidewall. Certainly, coatings, treatments, and finishing techniques could be employed by one skilled in the art during manufacture to maximize these factors and all such materials, shapes, contours, designs, configurations, and embodiments are contemplated herein. 
   Operationally, the cap&#39;s removal from a sloping sidewall container is very similar to its removal from a vertical sidewall container. Referring to  FIGS. 9 &amp; 10 , cap  1  is held onto container  26  at locking lip  8  and over covering opening  10 . Handle  7  with fulcrum  22  is adjacent to and in communication with sloping sidewall  25  in both the cap&#39;s engaged or closed position in  FIG. 9  and in the partially disengaged or partially open position in  FIG. 10 . Force applied to handle  7  in the direction of container sidewall  25  causes fulcrum  22  to slide up sidewall  25  to drive one or two locking lugs, depending on the embodiment used, shown generally at point  27  on the inside of cap  1  in  FIG. 10 , over and past container locking lip  8 . Once locking lug(s)  27  are free of container locking lip  8 , the rest of cap  1  can easily be removed from the remainder of the locking lug(s) on the opposite side of the interior of the cap. Although described here with reference to the locking lugs, the sloping sidewall design can be used with a continuous locking ring on the inside of the cap, but such embodiment is not preferred. 
   Many other embodiments will be apparent to one skilled in the art, and all of them are contemplated herein without departing from the spirit of the present invention. 
   Safety Locking Bar 
   In pharmaceutical and other applications where it would be important to restrict access to the contents of the container for certain segments of the population, such as children and those with certain disabilities, an impediment to easily opening the container will be a required or at least highly desired safety feature. One design that would work with the lever cap is disclosed in  FIGS. 11-16 . As shown in  FIGS. 11 and 12 , this safety locking bar can be employed on containers with either vertical or sloped sidewalls. 
   Operationally, cap  1  would be placed on container  9  with vertical sidewall  11 , as shown in  FIG. 11  or on container  26  with sloped sidewall  25 , as shown in  FIGS. 12 ,  13  &amp;  14 . Safety locking bar  28  would be affixed to container  9  or container  26  as an integral part of such container&#39;s construction or fastened onto such container after its initial manufacture. Safety locking bar  28  would be affixed to sleeve  12  as an integral part of such sleeve&#39;s construction or fastened onto such sleeve after its initial manufacture. The purpose of the safety locking bar is to prevent any vertical movement of the handle to cause the removal of the cap. Once the cap is placed on the container, it is rotated, as shown in  FIG. 14 , so that lever handle  7 , shown in the open or disengaged position in  FIG. 13 , slides under safety locking bar  28 , as shown in the closed or engaged position in  FIGS. 12 &amp; 14 . In a preferred embodiment, handle  7  would slide under safety locking bar  28  in the area at or near that point on handle  7  opposite the fulcrum, which area is subject to adjustment depending on the design of the handle, cap, and container. In this position, safety locking bar  28  would prevent any force on the handle from causing it to slide vertically upward in the direction of the cap. The handle can require movement in two or more directions as an added safety feature. 
   In addition, to prevent handle  7  from being easily rotated out from under safety locking bar  28 , thumb gate  29 , as shown on  FIGS. 15 &amp; 16  would serve as a stop block or locking mechanism. Thumb gate  29  would be an integral part of the container or sleeve, and would be depressible in nature with a built-in natural spring-like action or otherwise actuatable to allow rotation of the handle  7  out from under the locking bar  28 . As shown in  FIGS. 15 &amp; 16 , thumb gate  29  could be located adjacent to safety locking bar  28 , as shown on  FIG. 15  or partially underneath safety locking bar  28 , as shown on  FIG. 16 . As handle  7  is rotated toward and under safety locking bar  28 , thumb gate  29  would depress in toward the container. After handle  7  is cleared past thumb gate  29 , the thumb gate would spring outward and at least approximately even with handle  7  to prevent it from being rotated out from under safety locking bar  28 . 
   To remove handle  7  out from under safety locking bar  28  to position the lever cap for normal use at any other point around the container, a second operation would be required, in that thumb gate  29  would have to be depressed in toward the container at or around tab  30 , while the cap is rotated until the handle passes over the thumb gate and is out from under safety locking bar  28 . Thumb gate  29  would be affixed to container  9  or container  26  as an integral part of such container&#39;s construction or fastened onto such container after its initial manufacture. Thumb gate  29  would be affixed to sleeve  12  as an integral part of such sleeve&#39;s construction or fastened onto such sleeve after its initial manufacture. 
   In a more preferred embodiment, also shown in  FIG. 16 , an additional rib  31  could be fashioned onto the sidewall of the container in the area below safety locking bar  28 , so that when handle  7  is rotated under the safety locking bar, this rib  31  would be positioned under the lower lever portion of handle  7  to prevent it from being depressed toward the container. As a refinement to this design, this rib could be ramped on one or both sides, as shown at points  32  on  FIG. 16 , so that it is at its highest elevation, preferably in a middle portion thereof, under the handle when such handle is below safety locking bar  28 , and non-existent or flush with the sidewall of the container outside this area. Rib  31  would be affixed to container  9  or container  26  as an integral part of such container&#39;s construction or fastened onto such container after its initial manufacture. Rib  31  would be affixed to sleeve  12  as an integral part of such sleeve&#39;s construction or fastened onto such sleeve after its initial manufacture. 
   Ideally, in a preferred embodiment, the safety locking bar, thumb gate, and rib would be integral to the container or sleeve and molded as part of such container or sleeve&#39;s manufacture, respectively. Consistent with the manufacture of the cap and retro-fit sleeve, the safety locking bar, thumb gate, and rib could be formed from any appropriate material, including, without limitation, metal, plastic, fiberglass, or any suitable material or composite of materials by any suitable process, including stamping, molding, injection molding, thermoforming, or other appropriate process. A preferred material for manufacture would be plastic, and the most preferred choice from the polymer group would be a high-density polyethylene or variation, composite, or derivative thereof. Since in the preferred embodiment, the safety locking bar, thumb gate, and rib would be integral to the container or sleeve and molded as part of such container or sleeve&#39;s manufacture and some of such container/sleeve&#39;s intended uses might cause it to come in contact with food, beverages, medicine, and perhaps other products designed for human consumption, such materials for these applications may need to be compliant with the requirements of the U.S. Food and Drug Administration and could also include various additives, chemistries, and other means for antimicrobial protection for the benefit of the user, as well as for the integrity of the container, sleeve, safety locking bar, thumb gate, and rib. 
   Ergonomic and Aesthetics Features 
   One other aspect of the lever cap that will contribute to its use, acceptance, and commercial success is its ability to be customized to meet consumer preferences. For instance, as disclosed in  FIG. 17 , many ergonomic features could be incorporated, such as, for example, a gripping portion having a size and shape adapted to facilitate gripping and manipulation by a user. In the exemplary embodiment of  FIG. 17 , the gripping portion is an open finger ring design  33  at a distal end of the handle, where the user can insert his or her pointer or middle finger such that when the handle is depressed, the user can simply flip the cap off the container with a flick of his/her finger while holding the container with the rest of the same hand. Of course, other sizes and shapes of gripping portions can also be used. Likewise, by holding the cap by the finger ring, the user could recap the container by bringing the cap back into contact with the top of the container, engaging the locking lug(s) on the opposite side of the cap from the handle, and, once engaged, pulling down on the handle side of the cap to engage the locking lug(s) near the handle. Therefore, both the removal and recapping of the container can be accomplished with one hand. Furthermore, as shown in  FIG. 17 , numerous other consumer-friendly and aesthetic designs, advertising logos, colorations, material changes and inlays for different textures and feel can be used without departing from the original spirit of the present invention and are well known to those skilled in the art. In a preferred embodiment shown in  FIG. 17   a , the finger ring is a closed loop or ring  33   a . Additionally, other shapes, designs, or numbers of gripping portions can be used to facilitate manipulation of the handle, such as, for example, open rings (such as open ring  33  of  FIG. 17 ), ovals, hooks, and/or double or multiple rings on the handle, which handle could be of any shape, size, or configuration to receive such gripping portions. 
   Customizable for Different Applications 
   Another feature that adds to the lever cap&#39;s appeal is its ability to be customized for various applications. For instance, as disclosed in  FIG. 18 , the cap&#39;s use for beverages will require an impervious seal to prevent leaks. In other applications the seal might need to be impervious to one or a combination of particulates, liquids, fluids, and gasses. As is well known in the art, a gasket could be molded into the cap as an integral part of its construction, or a different one could be separately prepared from more suitable materials with more appropriate features for the application in question and inserted into the cap after manufacture. Separate gasket  34 , as shown in  FIG. 18 , is an example of this type of customization. In addition, many other customized features could be incorporated into the cap design, including, without limitation, options such as windows  35  around the side of the cap to allow escaping gas from pressurized contents to be released quickly before the entire cap is removed from the container. 
   The cap is customizable and scalable for different applications and its flexibility will add to its appeal and its acceptance. 
   While the present invention has been particularly described, in conjunction with a specific preferred embodiment, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. It is therefore contemplated that the appended claims will embrace any such alternative, modifications, and variations as falling within the true scope and spirit of the present invention.