Abstract:
A container top having an integral cover, for example, an integral dust cover, is provided. The container top includes a cap having a cylindrical skirt with a top, a bottom, a first outside diameter at the top of the skirt, a second outside diameter at the bottom of the skirt, and an inside surface adapted to engage a container; and a ring mounted to the top of the cylindrical skirt, the ring having an opening; and a cover removably mounted to the cap and occluding the opening in the ring. The container top may include a septum positioned in the opening, for example, a septum that can be pierced with a syringe. The container cap may be used in a wide range of industries, for example, the medical, pharmaceutical, the general scientific community, or in any industry where liquid or gaseous samples are handled.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a perforated cap having an integral cover. More particularly, the present invention relates to a perforated cap having a flexible septum and a removable protective cover protecting the flexible septum during handling and storage. 
       BACKGROUND OF THE INVENTION 
       [0002]    Container caps having apertures in their tops and flexible sealing elements mounted across the apertures are common in the medical, pharmaceutical, and general scientific community for storing samples, sera, and other liquid or gaseous contents. The flexible sealing element, or septum, typically provides a fluid-tight seal between the apertured cap and the container, for example, a vial, to which the cap is mounted while permitting access to the inside of the container by piercing the septum with, for example, a syringe, to introduce a fluid or withdraw a fluid. 
         [0003]    Due to the nature of the contents of these vials or containers in the medical and pharmaceutical fields, among others, it is typically imperative that such caps and septa be protected from pollutants and contaminants during use, transfer, storage, and other handling. For example, the Environmental Protection Agency (EPA) has established standards under 40 C.F.R. § 136 entitled “Guidelines for Establishing Test Procedures for the Analysis of Pollutants” and 40 C.F.R. § 141 entitled “National Interim Primary Drinking Water Regulations: Control of Trihalomethanes in Drinking Water,” among others, which describe acceptable testing procedures for the handling of samples during water analysis. These EPA standards specify a vial/cap/septum construction as well as detailed cleaning and sampling procedure that are designed to ensure that the sample is not contaminated or lost prior to analysis. These EPA regulations specify an open top cap and a septum comprised of silicone rubber laminated with polytetrafluoroethylene (PTFE), for example, Dupont&#39;s Teflon PTFE, where the face of the PTFE lamination is exposed to the sample in the vial. 
         [0004]    Among other things, these EPA procedures specify that the exposed elastomeric septum in the cap be protected from contamination during shipping, storage, and other handling. According to conventional practice, the caps and septa are typically protected by a removal cap or “dust cover,” for example, as shown and described with respect to  FIGS. 1 and 2  below. These removable, typically, plastic, caps are typically manually mounted to the cap and septum while the cap and septum are mounted on the vial prior to transport or storage. Subsequently, the caps are removed to permit access to the cap and septum. 
         [0005]    However, these removable dust covers and caps to which the dust covers are mounted are typically provided by separate suppliers and, prior to assembly by the end user, must each be cleaned. In accordance with conventional practice, the end user typically washes both the dust cover and the cap prior to assembly. This washing and handling by the end user is not only labor intensive, but also introduces the potential of introducing undesirable contaminants, including moisture, between the dust cover and the cap during the washing and handling process. Therefore, there exists a need for a cap having an integrated dust cover that overcomes the disadvantages of the prior art. Aspects of the present invention address this need while having other advantages compared to the prior art. 
       SUMMARY OF THE INVENTION 
       [0006]    Aspects of the present invention eliminate the need of a separate dust cover and its consequent handling and washing. One aspect of the invention is a container top comprising a cap with a cylindrical skirt having a top, a bottom, a first outside diameter at the top of the skirt, a second outside diameter at the bottom of he skirt, and an inside surface adapted to engage a container; and a ring mounted to the top of the cylindrical skirt, the ring having an opening; and a cover removably mounted to the cap and occluding the opening in the ring, the cover having substantially no structure extending beyond the first outside diameter of the skirt. In one aspect, the container top further includes a septum positioned in the cap to occlude the opening in the ring. In another aspect, the ring includes a first annular retaining structure, such as, an annular recess or an annular projection, and the cover includes a complementary second annular retaining structure adapted to engage the first annular retaining structure to retain the cover on the ca. In another aspect, the first annular retaining structure and the second annular retaining structure comprise the only means of engagement between the cap and the cover. 
         [0007]    Another aspect of the invention is a method of protecting a cap septum including providing a cap comprising a cylindrical skirt having top, a bottom, a first outside diameter at the top of the skirt, and a second outside diameter at the bottom of the skirt; and a ring mounted to the top of the cylindrical skirt, the ring having an opening; inserting a septum into the cap wherein the septum occludes the opening; mounting the cap with the septum on a container wherein at least some of the septum is exposed through the opening in the ring; and mounting a removable cover on the cap to protect the septum while providing no structure extending beyond the first outside diameter of the skirt. In one aspect, the cap further comprises a first annular retaining structure and the cover comprises a second annular retaining structure, and wherein mounting the removable cover on the cap comprise engaging the first annular retaining structure with the second annular retaining structure. 
         [0008]    A further aspect of the invention is a container top having a cap including a cylindrical skirt having a top, a bottom, a first outside diameter at the top of the skirt, a second outside diameter at the bottom of the skirt, and an inside surface adapted to engage a container; and a ring mounted to the top of the cylindrical skirt, the ring having an opening and a first annular retaining structure; and a cover removably mounted to the cap and occluding the opening in the ring, the cover having a second annular retaining structure adapted to engage the first annular retaining structure of the ring to retain the cover on the cap. In one aspect, the container top further comprises a septum positioned in the cap to occlude the opening in the ring. In another aspect, the first annular retaining structure comprises one of an annular recess and an annular projection. In one aspect, the cover comprises substantially no structure extending beyond the first outside diameter of the skirt. 
         [0009]    These and other aspects, features, and advantages of this invention will become apparent from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention will be readily understood from the following detailed description of aspects of the invention taken in conjunction with the accompanying drawings in which: 
           [0011]      FIG. 1  is a perspective view of a typical prior art cap assembly with a dust cover mounted to a bottle. 
           [0012]      FIG. 2  is an exploded perspective view of the prior art cap assembly with a dust cover mounted to a bottle shown in  FIG. 1 . 
           [0013]      FIG. 3  is perspective view of an integral cap and dust cover assembly according to one aspect of the invention. 
           [0014]      FIG. 4  is an exploded perspective view of the integral cap and dust cover assembly shown in  FIG. 3 . 
           [0015]      FIG. 5  is a cross sectional view of the dust cover shown in  FIG. 4 . 
           [0016]      FIG. 6  is a cross sectional view of the cap shown in  FIG. 4 . 
           [0017]      FIG. 7  is a cross sectional view of the assembled dust cover and cap shown in  FIGS. 5 and 6 . 
           [0018]      FIG. 8  is a perspective view of another cap and cover according to another aspect of the invention. 
           [0019]      FIG. 9  is a perspective view of the cap and cover shown in  FIG. 8  with the cover opened. 
           [0020]      FIG. 10  is a cross sectional view of the cap and cover shown in  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION 
       [0021]      FIG. 1  is a perspective view of a typical prior art cap assembly  10  having a dust cover  12  mounted to a bottle or vial  14  (only the top portion of which is shown).  FIG. 2  is an exploded perspective view of the prior art cap assembly  10  having dust cover  12  mounted to bottle  14  shown in  FIG. 1 . As shown, prior art cap assembly  10  may typically include a cap  16  having a hole  18  in its top and a septum  20  mounted in cap  16  to obstruct hole  18 , for example, mounted by means of the methods disclosed in commonly-assigned U.S. Pat. Nos. 5,647,939 and 6,234,335—the disclosures of which is included by reference herein. Septum  20  may typically be an inert elastomeric material as disclosed in the above referenced patents, for example, a PTFE-laminated silicone rubber, or its equivalent. As is known in the art, septum  20  provides a peircible medium through which, for example, a syringe may be passed to access the contents of bottle  14  while minimizing or preventing leakage of the contents through the hole created by the syringe. According to prior art practice, dust cover  12  is provided for cap assembly  10  to minimize or prevent the contamination of cap  16  and septum  20  during handling, transport, and storage. According to the prior art, dust cover  12  typically comprises a molded plastic cover sized to fit snugly about cap  16  and protect hole  18  and septum  20  from contamination. Typically, dust cover  12  is manually mounted to cap  16  and manually removed from cap  16  by a technician, for example, by prying dust cover  12  from cap  16  by grasping annular lip  22  on dust cover  12 . 
         [0022]    However, the presence, handling, and manipulation of dust cover  12  can be problematic. For example, dust cover  12  may be made from a material that can contaminate cap assembly  10 , specifically contaminate septum  20 . For example, when dust cover  12  is fabricated from an inadequate thermoplastic, the dust cover  12  can react or otherwise contaminate the material from which septum  20  is made, for example, a silicone rubber. Also, the presence of dust cover  12  upon arrival at a facility requires that dust cover  12  be removed from cap assembly  10 , discarded, or washed with cap assembly  12  prior to use or re-use. For these and other disadvantages of the prior art shown in  FIGS. 1 and 2 , the present invention in its various aspects was conceived and developed. 
         [0023]      FIG. 3  is perspective view of an integral cap and dust cover assembly, or container top,  30  according to one aspect of the invention.  FIG. 4  is an exploded perspective view of the integral cap and dust cover assembly  30  shown in  FIG. 3 . According to aspects of the present invention, container top  30  includes a cap  32  and a cover, or dust cover,  33 . In one aspect of the invention, cap  32  may include a septum  35 , for example, an elastomeric septum similar to septum  20  discussed above.  FIG. 5  is a cross sectional view of cover  33  shown in  FIG. 4 .  FIG. 6  is a cross sectional view of cap  32  shown in  FIG. 4 .  FIG. 7  is a cross sectional view of the assembled cover  33  and cap  32  shown in  FIGS. 5 and 6 . As shown in  FIGS. 3 and 4  container top  30  may include an outside surface  31  that is typically textured or knurled to facilitate handling of top  30 , for example, when threading or unthreading container top  30  from bottle  14 . As also shown, container top  30  may include a recess  37  in surface  31  to facilitate access to cap  32 , for example, for removing cap  32 . 
         [0024]    As shown most clearly in  FIG. 6 , cap  32  includes a cylindrical skirt  34  having a top or first end  36  and a bottom or second end  38 , and a ring  40  mounted to the top  36 . Ring  40  includes an opening  42  which exposes septum  35  (shown in phantom in  FIG. 6 ) mounted within cap  32 , for example, by means of the methods disclosed in U.S. Pat. Nos. 5,647,939 and 6,234,335. Septum  35  may include markings to facilitate positioning a syringe for insertion through septum  35 , for example, one or more circles or “cross hairs.” The markings may be recessed into the surface of septum  35  or protrude above the surface of septum  35 . 
         [0025]    According to an aspect of the invention, skirt  34  includes a first outside diameter  46  at the top  36  of skirt  34 , a second outside diameter  48  at the bottom  38  of skirt  34 , a height  49 , and an inside surface  50  adapted to engage a container (not shown), for example, a bottle similar to bottle  14  shown in  FIGS. 1 and 2 . The inside diameter  50  may include one or more helical threads  51  adapted to engage a threaded bottleneck. In one aspect, first outside diameter  46  may be substantially equal to second outside diameter  48 ; however, first outside diameter  46  may be smaller than second outsider diameter  48 , for instance, to facilitate removal of cap  32  from a mold when cap  32  is fabricated by molding. Outside diameter  46  may also be greater than outside diameter  48 . 
         [0026]    As also shown in  FIG. 6 , cap  32  may include an annular retaining structure  52 , for example, a first annular retaining structure, adapted to engage an annular retaining structure, for example, a second annular retaining structure, in cover  33 , for example, annular retaining structure  58  discussed below. In one aspect, the annular retaining structure  52  of cap  32  may be associated with ring  40 , for example, annular retaining structure  52  may be mounted on the inside diameter (for example, on the insider diameter of hole  42 ) or on the outside diameter of ring  40 . In one aspect of the invention, annular retaining structure  52  may comprise one or more annular recesses or one or more annular protections, for example, one substantially continuous annular recess or projection. For instance, as shown in  FIG. 6 , annular retaining structure  52  may comprise an annular recess  53  adapted to engage one or more annular projections on cover  33 . Annular recess  53  may have one or more internal corners or be radiused as shown in  FIG. 5 . In one aspect, the engagement of annular retaining structure  52  with its complementary structure on cover  33  may be substantially fluid tight, that is, be so structured to minimize or prevent the passage of a fluid, for example, a liquid or a gas. In another aspect of the invention, for example, where fluid isolation is not paramount, the engagement between annular retaining structure  52  and its complementary structure may not be fluid tight. For example, in one aspect, annular retaining structure  52  may comprise a plurality of spaced recesses or projections, for instance, a plurality of spaced recesses or projections adapted to engage a plurality of complementary spaced recesses or projections in cover  33 . 
         [0027]    As shown in  FIG. 5 , cover  33  is shown in larger scale to illustrate details of the invention. Cover  33  includes a thin membrane portion  54  and an annular or ring portion  56 . According to one aspect of the invention, annular portion  56  provides means for mounting cover  33  to cap  32  and membrane portion  54  provides the protective barrier for hole  40  (and septum  35 ) in cap  32 . Cover  33  also includes an outside diameter  60 . 
         [0028]    In a fashion similar to annular retaining structure  52  of cap  32 , cover  33  includes an annular retaining structure  58 , for example, a second annular retaining structure, adapted to engage an annular retaining structure, for example, a second annular retaining structure, in cap  32 , for example, annular retaining structure  52  discussed above. In one aspect, the annular retaining structure  58  of cover  33  may be associated with annular or ring portion  56 , for example, annular retaining structure  58  may be mounted on the inside diameter or the outside diameter of annular portion  58 . In one aspect of the invention, annular retaining structure  58  may comprise one or more annular recesses or one or more annular projections, for example, one substantially continuous annular recess or projection. For instance, as shown in  FIG. 5 , annular retaining structure  58  may comprise an annular projection  59  adapted to engage one or more annular recesses  53  in cap  32 . In one aspect, as discussed above with respect to cap  32 , the engagement of annular retaining structure  58  with its complementary structure on cap  32  may be substantially fluid tight or non-fluid tight. In another aspect of the invention, annular retaining structure  58  in cover  33  may comprise a plurality of spaced recesses or projections, for instance, a plurality of spaced recesses or projections adapted to engage a plurality of complementary spaced recesses or projections in cap  32 . In one aspect, the first annular retaining structure  52  in cap  32  and second annular retaining structure  58  in cover  33  may comprise the only means of engagement between cap  32  and cover  33 . 
         [0029]    According to an aspect of the present invention, cover  33  is removably mounted to cap  32  and occludes opening  42  in ring  40  of cap  32 . Moreover, cover  33  may include substantially no structure extending beyond the first or upper outside diameter  46  of skirt  34 . For example, cover  33  may be so mounted to cap  32  that the outside diameter  60  of cover  33  is substantially no greater than the first outside diameter  46  of skirt  34 . By providing cover  33  within the dimensions of cap  32 , several advantages are provided, including limiting the modification of the molding tooling required to fabricate cap  32  and ensuring compatibility with existing cap and bottle handling equipment, for example, automated handling equipment, among other advantages. It is to be understood that, though in one aspect of the invention, outside diameter  60  of cover  30  may be substantially no greater than the first outside diameter  46  of skirt  34 , practical considerations of manufacturing tolerances, material flexibility, and other material deviations, among other things, may create an outside diameter  60  somewhat greater than first outside diameter  46 . Since such minor deviations may still effect one aspect of the desired invention, that is, compatibility with existing tooling and handling equipment, it will be understood by those of skill in the art that such deviations are within the scope of the present invention. 
         [0030]      FIG. 8  is perspective view of container top  100  according to another aspect of the invention. According to this aspect of the present invention, container top  100  includes a cap  62  and a cover  63 . In one aspect, cover  63  may engage cap  62  in a fashion similar to the way cover  33  engages cap  32  above, that is, by means of complementary annular retaining structures  52  and  58 . However, contrary to the aspect shown in  FIGS. 3-7 , container top  100  may include a hinge assembly  61  (shown in phantom) adapted to retain cover  63  when cover  63  is disengaged from cap  62 .  FIG. 9  is a perspective view of the container top  100  shown in  FIG. 8  with the cover  63  in the opened position, for example, as retained by hinge assembly  61 .  FIG. 10  is a cross sectional view of container top  100  shown in  FIGS. 8 and 9 . In one aspect of the invention, cap  62  may include a septum  65  (shown in phantom in  FIG. 10 ), for example, an elastomeric septum similar to septa  22  and  35  discussed above. 
         [0031]    As shown most clearly in  FIG. 10 , cap  62  includes a cylindrical skirt  64  having a top or first end  66  and a bottom or second end  68 , and a ring  70  mounted to the top  66 . Ring  70  includes an opening or hole  72  which exposes septum  65  (again, shown in phantom in  FIG. 10 ) mounted within cap  62 , for example, by means of the methods disclosed in U.S. Pat. Nos. 5,647,939 and 6,234,335. According to an aspect of the invention, skirt  34  includes a first outside diameter  76  at the top  66  of skirt  64 , a second outside diameter  78  at the bottom  68  of skirt  64 , a height  79 , and an inside surface  80  adapted to engage a container (not shown), for example, a bottle similar to bottle  14  shown in  FIGS. 1 and 2 . The inside diameter  80  may include one or more helical threads  81  adapted to engage a threaded bottleneck. In one aspect, first outside diameter  76  may be substantially equal to second outside diameter  78 ; however, first outside diameter  76  may be smaller than second outsider diameter  78 , for instance, to facilitate removal of cap  62  from a mold when cap  62  is fabricated by molding. Outside diameter  76  may also be greater than outside diameter  78 . 
         [0032]    As also shown in  FIG. 10 , cap  62  may include an annular retaining structure  82 , for example, a first annular retaining structure, adapted to engage an annular retaining structure, for example, a second annular retaining structure, in cover  63 , for example, annular retaining structure  88  on cover  63 . In one aspect, the annular retaining structure  82  of cap  62  may be associated with ring  70 , for example, annular retaining structure  82  may be mounted on the inside diameter (for example, on the inside diameter of hole  72 ) or the outside diameter of ring  70 , for example, a ring  71  mounted to or projecting from ring  70 . In one aspect of the invention, annular retaining structure  82  may comprise one or more annular recesses or one or more annular protections, for example, one substantially continuous annular recess or projection or one or more discontinuous annular recesses or projections (as discussed above with respect to container cover  10 ) mounted in or on ring  71 . Similarly, in one aspect of the invention, annular retaining structure  88  on cover  63  may comprise one or more annular recesses or one or more annular protections, for example, one substantially continuous annular recess or projection or one or more discontinuous annular recesses or projections (as discussed above with respect to container cover  10 ) mounted in or on ring  86  (described below). In one aspect, the engagement of annular retaining structure  82  with its complementary retaining structure  88  on cover  63  may be substantially fluid tight or non-fluid tight, depending upon the medium container top  100  is used to retain and the application of container top  100 . 
         [0033]    As shown in  FIG. 10 , cover  63  may include a thin membrane portion  84  and an outer annular or ring portion  85  and an inner annular ring portion  86 . According to one aspect of the invention, inner annular portion  86  may provide means for removably engaging cover  63  to cap  62  and membrane portion  84  may provide a protective barrier for hole  72  (and septum  65 ) in cap  62 . Cover  63  outer annular ring  85  also includes an outside diameter  90 . 
         [0034]    As also shown in  FIG. 10 , annular retaining structure  88  on cover  63  is adapted to removably engage annular retaining structure  82  on cap  62 . In the aspect shown in  FIG. 10 , though the retaining structures may comprise one or more recesses or projections as discussed above, annular retaining structures  82  on cap  62  and annular retaining structure  88  on cover  63  may comprise a friction fit between annular rings  71  and  86 . For example, rings  71  and  86  may be sized whereby sufficient friction is provided between their respective contacting surfaces to provide sufficient engagement to minimize or prevent disengagement. In one aspect, the annular retaining structure  82  in cap  64  and annular retaining structure  88  in cover  63  may comprise the only means of engagement between cap  62  and cover  63 , for example, friction between rings  71  and  86  may be the only means of engagement between cap  62  and cover  63 . 
         [0035]    Similar to the aspect of the invention illustrated in and described with respect to  FIGS. 3 to 7 , according to an aspect of the present invention, cover  63  is removably mounted to cap  62  and occludes opening  72  in ring  70  of cap  62 . Moreover, in one aspect, cover  63  may include substantially no structure extending beyond the first or upper outside diameter  76  of skirt  64 . For example, cover  63  may be so mounted to cap  62  that the outside diameter  90  of cover  63  is substantially no greater than the first outside diameter  76  of skirt  64 . By providing cover  63  within the dimensions of cap  62 , several advantages are provided, including limiting the modification of the molding tooling required to fabricate cap  62  and ensuring compatibility with existing cap and bottle handling equipment, for example, automated handling equipment, among other advantages. 
         [0036]    As also shown in  FIG. 10 , container top  100  may include some form of hinge assembly  61  (shown in phantom) adapted to retain cover  63  on cap  62  when cover  63  is dislodged from engagement with cap  63 . For example, as shown in  FIG. 10 , in one aspect, hinge assembly  61  may comprise a strap  102  having a first end  104  mounted to cover  63  and a second end  106  mounted to cap  62 . In this aspect of the invention, hinge assembly  61  may retain cover  63  on cap  62  when cover  63  is removed from or disengaged from cap  62  to expose opening  72  in cap  62 . In one aspect, cover  63 , cap  62 , and strap  102  may be fabricated as one integral component, for example, by molding. Strap  102  may have a length of between about 0.25 inches and about 0.50 inches; a width of between about 0.10 inches and about 0.25 inches; and a thickness of between about 0.005 inches and about 0.050 inches. 
         [0037]    Container covers  10  and  100  may be fabricated from any conventional metallic or non-metallic material, but is typically fabricated from plastic. For example, container covers  10  and  100  may be fabricated from one or more of the following plastics: a polyamide (PA), for example, nylon; a polyamide-imide; a polyethylene (PE); a polypropylene (PP); a polyester (PE); a polytetraflouroethylene (PTFE); an acrylonitrile butadiene styrene (ABS); a polycarbonate (PC); or a vinyl, such as, polyvinylchloride (PVC), among other plastics. 
         [0038]    The outside diameter  60  of cover  33 , the outside diameters  46  and  48  of cap  32 , the outside diameter  76  of cover  63 , and the outside diameter  90  of cap  62  may vary from about 0.25 inches to about 12 inches, but are typically between about 0.5 inches and about 3 inches, for example, about 1 inch. The thickness of membrane portion  54  of cover  33  and the thickness of membrane portion  84  of cover  63  may vary from about 0.01 inches to about 1.0 inch, but is typically between about 0.010 inches and about 0.020 inches, for example, about 0.015 inches. The height  49  of cap  32  and the height  79  of cap  62  may vary from about 0.25 inches to about 6 inches, but is typically between about 0.40 inches and about 0.75 inches, for example, about 0.60 inches. 
         [0039]    According to aspects of the invention, container covers  10  and  100  provide improvements over the container covers according to the prior art, in particular, when container covers  10  and  100  include flexible septa. Aspects of these inventions minimize or eliminate the need to handle and wash separate dust covers while imposing little or no impact upon the manufacture and handling of such container covers. These and other advantages of aspects of the invention will be apparent to those of skill in the art. 
         [0040]    While several aspects of the present invention have been described and depicted herein, alternative aspects may be effected by those skilled in the art to accomplish the same objectives. Accordingly, it is intended by the appended claims to cover all such alternative aspects as fall within the true spirit and scope of the invention.