Abstract:
A plastic closing lid for a storage container, the closing lid having a length dimension and a shorter width dimension. The lid defining a receiving channel extending lengthwise and a stiffening component captured within said receiving channel.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    The present application is a Continuation-in-Part of and claims the benefit of U.S. Provisional Patent Application Ser. No. 60/900,907, filed Feb. 12, 2007, entitled “REINFORCING STRUCTURE FOR PLASTIC LID” which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Storage containers for the containment of discrete articles, such as medical devices, equipment and instruments typically include a storage tray and closing lid combination. Typical materials for either the tray or the lid or both include steel, aluminum, other metals, and plastics. Size variations, whether in length, width or depth, are also common for these types of storage containers. 
         [0003]    One concern that has been recognized is the flexible nature of plastic closing lids when the longer dimension (length) reaches a certain size, depending on the material, material thickness, and other design variables. This lid flexibility can be influenced to some extent on the plastic selected for the molding or forming process as well as the material thickness that is molded or formed. Other influencing factors include the length dimension and the presence or absence of stiffening ribs, bosses, channels, etc., that are part of the unitary lid construction and that might be able to provide some degree of stiffening or reinforcing to the lid, adding to its rigidity. For the most part, these added forms need to run length-wise with a sufficient length to actually add to the stiffness of the lid and reduce or lessen its flexibility. Handling of the closing lid and assembly of the lid onto the tray are facilitated by added lid stiffening or rigidity. There may also be a customer benefit in terms of the overall product construction not appearing to be cheap or flimsy. As used herein “reinforcing” of the closing lid is achieved by adding a stiffening component to increase the rigidity. 
         [0004]    Perhaps a less intuitive aspect of having a flexible closing lid as one portion of a storage container is the number of slide latches (as one example of the type that can be used) that is required for securely connecting or attaching the closing lid to the tray. When the closing lid is constructed of a size, shape, and material that results in overall lid flexibility, it is likely that four slide latches will be used. There is typically a slide latch on each end and a slide latch on each side. While the reference herein is made to a slide latch, it should be understood that any type of latching or closing mechanism should be suitable at those four spaced-apart locations. By reinforcing the closing lid according to the present disclosure, it is envisioned that only two oppositely-disposed latches would be required to properly secure the closing lid to the tray in order to create the desired storage container. The anticipated arrangement when only two latches are used is to position one latch on each side. When tray-lifting handles are provided and are used as lid-latching members, the stiffening members disclosed herein are considered to be sufficient to provide the requisite lid rigidity such that no other latches of any type are needed. 
         [0005]    The addition of molded-in or formed-in shapes to the unitary lid construction normally require some amount of added material and this in turn equates to added mold expense. One consideration is the amount of added material that is required to achieve the desired closing lid reinforcement. Another consideration is whether molded-in or formed-in shapes might interfere with any forms that are used for stacking of one container onto another container. Aesthetically, there may be concerns if the top surface of the lid is filled with stiffening forms in lieu of customer decals or labels, for example. Further, once the mold or vacuum-formed tooling is fixed for these stiffening shapes, it is not economical to change or offer design alternatives to customers, particularly to those customers that do not need, want, or want to pay for these lid stiffening features. 
         [0006]    The disclosed embodiments address this lid flexibility/lid stiffness issue by capturing a metal or rigid plastic tube or rod in a molded, lengthwise channel or groove, allowing the rigidity of the stiffening component to noticeably reduce the degree of flexibility or flexing of the lid. In order to effectively stiffen the lid, the stiffening component needs to be of adequate length and preferably centered between the ends of the lid. The stiffening component can alternatively be fabricated out of other materials and formed in other shapes. This stiffening component can be mechanically captured by the form or shaping of the channel, or bonded into position with a suitable adhesive, or configured as a molded-in or formed-in insert. A further way of capturing the stiffening component is to lay it in a groove or channel and then enclose the tube with an outer layer or cover. This outer layer or cover can be molded or adhesively bonded or ultrasonically welded into position. 
         [0007]    A containment case, as referenced herein, that is suitable for use with the disclosed reinforced plastic lid, is constructed and arranged according to U.S. patent application Ser. No. ______, entitled Containment-Case With Latching Handle, filed (Feb. 11, 2008), and further identified by Attorney Reference 8036-48. 
       BRIEF SUMMARY 
       [0008]    A plastic closing lid for a storage container, the closing lid having a length dimension and a shorter width dimension. The lid defining a receiving channel extending lengthwise and a stiffening component captured within said receiving channel. 
         [0009]    One object of the present invention is to provide an improved plastic closing lid. Related objects and advantages will be apparent from the following description. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective view of a plastic closing lid according to the present invention. 
           [0011]      FIG. 1A  is an end elevational view, in full section, of an integral rib formed lengthwise in the  FIG. 1  plastic closing lid and defining a hollow interior channel. 
           [0012]      FIG. 1B  is an end elevational view corresponding to  FIG. 1A  with a hollow metal tube installed in the interior channel. 
           [0013]      FIG. 2  is a bottom plan view of a generic plastic closing lid showing its inner surface. 
           [0014]      FIG. 3  is a partial, bottom plan view of a plastic closing lid showing an alternative embodiment of the present invention. 
           [0015]      FIG. 4  is a partial, bottom plan view of a plastic closing lid showing another embodiment of the present invention. 
           [0016]      FIG. 5  is a partial, end elevational view of a receiving channel and metal tube combination according to the present invention. 
           [0017]      FIG. 5A  is a partial, end elevational view of an alternative receiving channel and metal tube combination according to the present invention. 
           [0018]      FIG. 5B  is a partial, end elevational view of another alternative receiving channel and metal tube combination according to the present invention. 
           [0019]      FIG. 6  is a partial, end elevational view of a receiving channel and metal tube combination according to the present invention. 
           [0020]      FIG. 6A  is a partial, end elevational view of an alternative receiving channel and metal tube combination according to the present invention. 
           [0021]      FIG. 6B  is a partial, end elevational view of another alternative receiving channel and metal tube combination according to the present invention. 
           [0022]      FIG. 7  is a partial, end elevational view of a receiving groove and metal tube combination according to the present invention. 
           [0023]      FIG. 7A  is a partial, end elevational view of an alternative receiving groove and metal tube combination according to the present invention 
           [0024]      FIG. 7B  is a partial, end elevational view of another alternative receiving groove and metal tube combination according to the present invention 
           [0025]      FIG. 8  is an end elevational view of an enclosing cover suitable for use as part of the present invention. 
           [0026]      FIG. 9  is an end elevational view of an alternative enclosing cover suitable for use as part of the present invention. 
           [0027]      FIG. 10  is a partial, end elevational view, in full section, of a metal tube captured within a molded plastic lid. 
           [0028]      FIG. 11  is a perspective view of a plastic closing lid according to another embodiment of the present invention. 
           [0029]      FIG. 12  is a partial, end elevational view, in full section, of the  FIG. 11  plastic closing lid with a stiffening tube installed. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    For the purposes of promoting an understanding of the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations and further modifications in the illustrated device and its use, and such further applications of the principles of the disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the disclosure relates. 
         [0031]    Referring to  FIG. 1 , there is illustrated a unitary plastic closing lid  20 , according to the present disclosure, that is constructed and arranged to be applied to a containment tray (not illustrated) for creating a containment case for receiving and storing discrete articles, typically medical (or dental) equipment, devices, and/or instruments. Prior art versions of lid  20  typically include areas for receiving cooperating slide latches (not illustrated), preferably one on each side or end, that are used to secure the closing lid to the tray. Based on the use of stiffening members for reinforcing lid  20 , it is possible to reduce the four latches to two, likely located along the sides near areas  21 . When the lifting handles are used to latch the lid, it is possible to eliminate all four slide latches, due to the use of stiffening members. Lid  20  also includes a plurality of spaced-apart openings  22  for the flow of steam (or sterilant) into and out of the case. 
         [0032]    One characteristic of plastic closing lids of the type generally illustrated herein is the flexibility of the lid due to its size and material. Depending on the length (L) and width (W) dimensions, the material, the material thickness, and any added (molded) forms for stiffening, the typical plastic lid will exhibit some degree of flexibility. In terms of handling, assembly to or removal from the tray, and overall customer impressions of product quality, a lid with too much flexibility is not desired. While flexibility is a relative concept, if the lid is too flexible, it will be considered flimsy and not representative of a quality product. Further, if the lid is too flexible, the aforementioned concerns about handling and assembly to or removal from the tray will also be realized. Lids with the typical degree of flexibility would also typically require four latches, such as the referenced slide latches (see the four locations of  FIG. 1 ). 
         [0033]    The issue then for the manufacturer of such a plastic lid is how to reinforce the lid by adding rigidity (i.e., stiffening) to the lid in order to reduce the flexibility, without creating other design problems or issues and without significantly adding to the overall cost of the lid. The approach selected, as disclosed herein, is to capture a rigid stiffening component in a molded or vacuum-formed channel or groove or similar receiving recess. Whether the channel or groove or recess is of a continuous length or formed or in a plurality of spaced-apart segments, they are formed as a unitary part of the molded or formed plastic lid. The stiffening component is preferably a metal tube, but alternatively can be fabricated from a rigid plastic or other material and can be a rod or some other shape. 
         [0034]    Lid  20  includes a pattern of molded channels, grooves and related forms (raised ribs) extending around the periphery of the lid, across the upper surface of the lid, and around the latching handle areas. The peripheral raised ribs  20   a  that are adjacent the outer peripheral edge of lid  20  include and define open channels  20   b  that are formed (i.e., integrally molded) into the raised rib shape that extends above upper surface  20   c , as is illustrated in  FIGS. 1A and 1B . 
         [0035]      FIG. 1A  illustrates a cross sectional configuration of one raised rib  20   a  and its interior open and defined channel  20   b . This open interior channel, as formed by rib  20   a , extends above upper surface  20   c . As will be described in greater detail herein, the open channel interior  20   b  is sized and shaped to receive a rigid stiffening component. 
         [0036]    As noted, lid  20  includes outer raised rib forms, similar to raised rib  20   a , specifically raised ribs  20   d  around the receiving area  20   e  for a latching handle (not illustrated). These ribs  20   d  are constructed and arranged to receive properly sized and shaped stiffening members, if that would be desired. However, the maximum benefit from the addition of a stiffening member is a length-wise member that is generally parallel to the length dimension “L” of lid  20 . Four smaller raised ribs  20   f  are formed in the interior panel portion of lid  20 . While these raised ribs  20   f  could be configured to also receive a smaller diameter stiffening member, it is anticipated that larger stiffening members in the peripheral ribs  20   a  will add sufficient reinforcement and rigidity to lid  20 . 
         [0037]      FIG. 1B  illustrates the raised peripheral rib  20   a  with a hollow metal tube  23  snapped into channel  20   b . Due to the forming and spacing of edges  20   g  in the manner illustrated, clearance opening  20   h  has a width dimension that is smaller than the diameter of hollow metal tube  23 . Accordingly, the assembly of tube  23  into channel  20   b  is accomplished by forcing tube  23  through opening  20   h  such that the tube  23  snaps into the channel  20   b.    
         [0038]    Referring to  FIG. 2 , the inner surface  25  of an alternative lid  24  is illustrated and includes, as part of its unitary construction, two substantially parallel molded-in (or vacuum formed) channels  26  and  27 . In terms of “inner” and “outer” as used herein, an “inner” surface of the lid is the surface that faces the interior of the containment case, toward the instruments and/or devices, equipment, etc. These two channels extend along the length dimension (L) and are substantially parallel to the longitudinal centerline  28 . Preferably, each channel extends for at least forty percent (40%) of the “L” dimension. The  FIG. 2  illustration shows each channel  26  and  27  as a raised form (inwardly directed), similar to what is shown as a cross section in  FIGS. 5 and 6 , with a hollow metal tube  29  installed, as one example. Each raised channel  26  and  27  can also be arranged in spaced-apart sections or segments  30 , as illustrated in  FIG. 4 . The  FIG. 2  channels are assigned reference numerals  26  and  27  to represent a general or generic form. The specific channel constructions of  FIGS. 5 and 6  are given distinguishing letters a and b, respectively. Further variations are illustrated in later drawings. 
         [0039]    The raised rib construction of lid  20  includes raised forms that are predominantly above upper surface  20   c . These rib forms are illustrated in  FIGS. 5B ,  6 B, and  7 B. In  FIG. 2 , the rib construction of lid  24  includes forms extending inwardly from inner surface  31 . These rib forms are illustrated in  FIGS. 5 ,  6  and  7 . A third variation, something that is actually in between these two other configurations, is also possible and is illustrated in  FIGS. 5A ,  6 A and  7 A. 
         [0040]    With continued reference to  FIG. 2 , centered on centerline  28  in broken line form is an optional third channel  33 . If additional stiffening or reinforcement is desired for lid rigidity, this third channel  33  can be added as a complement to channels  26  and  27 . Each channel is constructed and arranged to receive a stiffening member, which is preferably hollow metal tube  29 . Other options include a metal rod, a rigid plastic tube, a rigid plastic rod and other cross section shapes, such as square, rectangular, triangular, for example, in either metal or rigid plastic. One form for each raised channel  26  and  27  is illustrated in  FIG. 5 , specifically identified as  26   a , wherein raised portions  34  and  35  are substantially parallel, straight walls that are spaced apart a dimension that is only slightly larger than the diameter of tube  29 . This construction requires the use of an adhesive to hold the tube  29  in place or alternatively some form of enclosing cap  43 ,  44  or structure, see  FIGS. 8 ,  9 , and  10 . The same sidewall construction of raised portions  34  and  35  can be used for the spaced-apart segments  30 . 
         [0041]    One option for the forms of  FIGS. 5 ,  6 , and  7  that include raised portions  34 ,  35 ,  36 , and  37 , and a recess (concave) shape such as groove  41 , is to form the outer or upper surface of lid  20  (or lid  42  in the case of  FIG. 7 ) with a complementing shape (see  FIGS. 5A ,  6 A and  7 A, respectively. This added forming or shaping contributes to the overall reinforcement or stiffening of the lid and additionally results in having slightly greater clearance on the interior of the containment case. In  FIG. 5A , rib  34   a  spans the spacing of portions  34  and  35  so that tube  29  (the stiffening member) seats deeper into the body of the lid  20 . A similar arrangement and result is achieved by rib  36   a  in  FIG. 6A  and by rib  41   a  in  FIG. 7A . Another option, as illustrated in the preferred embodiments of  FIGS. 1A and 1B , is to form all of the rib structure on the upper, outer surface of the lid, see also  FIGS. 5B ,  6 B and  7 B. 
         [0042]    Referring to  FIG. 6 , the sidewall portions  36  and  37  of channel  26   b  are higher and are curved, as compared to portions  34  and  35 . If channel  27   b  was illustrated, it would have the same construction as channel  26   b . The curvature of each portion  36  and  37  creates a generally circular (in lateral cross section) space for receipt of tube  29 . The edge-to-edge separation that defines gap  38  is smaller than the diameter of tube  29 . As a result, when tube  29  is assembled into this channel form, the tube has to be forced through gap  38 , something which is permitted by the flexing and separation of portions  36  and  37 . The resiliency of this molded plastic construction provides a type of spring back with regard to portions  36  and  37 , thereby causing the tube  29  to be captured and securely retained in its corresponding channel  26   b  (and  27   b ). The same is achieved by the  FIG. 6A  construction. The  FIG. 6  style of channel can be used for the spaced-apart segments  30 . While the use of adhesive is not required for the  FIG. 6  construction, adhesive can be used for added security and the capture of tube  29 . While the use of a hollow metal tube is illustrated, any of the other shapes and materials previously listed are suitable for the referenced stiffening member or component. 
         [0043]    Referring now to  FIG. 3 , the channel construction of lid  20  is replaced by a recessed groove  41  as part of the construction of plastic closing lid  42 . It is to be understood that lid  42  is identical to lid  20 , except that the raised channel construction of channels  26  and  27 , and possibly channel  33 , including the various forms of these channels based upon  FIGS. 5 ,  6 , and  4  is replaced with a recessed groove  41 . A second groove (although not illustrated) is used in the location of channel  27  and a third groove is an option and would be located generally in the same location as optional channel  33 . Groove  41  is illustrated in  FIG. 7  with tube  29  place therein. All of the grooves, channels and forms incorporated as part of the unitary lids  20  and  42  extend for at least forty percent (40%) of the “L” dimension. In the case of any segments or sections such as segments  30 , the combined length is at least forty percent of the “1” dimension. 
         [0044]    Since tube  29  cannot be captured by groove  41 , so as to remain within groove  41  in a securely retained condition, either an adhesive must be used or some type of capturing cover, see  FIGS. 8 and 9 . The capturing covers  43  and  44  can be adhesively bonded in place over tube  29  and groove  41  or the selected cover can be secured in place by ultrasonic welding. Covers  43  and  44  represent only two possibilities and virtually any construction is acceptable so long as tube  29  is securely captured. Covers  43  and  44  can be constructed as either short length segments, using a plurality along the length of the tube  29 , or these two covers can be configured as substantially full length sleeves. 
         [0045]    A still further option for securely capturing tube  29  is to insert mold the tube  29  in position at the time of molding or forming the corresponding lid  45 , noting that lid  45  is otherwise virtually identical to lids  20  and  42 . The molded-in insert concept involves positioning the selected tubes  29  in their desired position within the mold or forming tooling and then molding or forming the plastic of the lid around each tube  29 . 
         [0046]    With regard to the closing lids illustrated in  FIGS. 1 ,  1 A,  1 B and  2 , and depending on the particular edge configuration, something that could change depending on the style of tray, edge periphery channels, or at least channels adjacent the outer edge of the lid, may already exist as part of that lid construction. If such a channel already exists then, in order to practice the present invention, it is necessary to select a properly sized stiffening member, such as a metal tube, and install it. The installation scheme can correspond to any of those illustrated and/or described herein. These options include securing those tubes in position by a snap-fit, by the use of adhesive, or by covering over sufficient portions of the tubes with a plastic cover that would either be adhesively bonded in position or ultrasonically welded, for example. 
         [0047]    A still further option would be to place the stiffening tube  29  into a formed corner, most likely formed as a right angle such that the tube  29  would be contacted on two sides 90 degrees apart. This type of interior right angled corner may exist, depending on the form of the lid edge and how it is shaped to attach to the tray. In this construction, those same capturing techniques would be required. Either a snap-fit or the use of an adhesive to secure the tube  29  in position or the use of some covering component that could either be adhesively bonded in position or ultrasonically welded, for example. 
         [0048]    Referring now to  FIGS. 11 and 12 , a reinforced plastic closing lid  50  according to the present invention as illustrated, utilizing two stiffening members in the form of metal tubes installed in opposite length-wise channels formed by defining, raised ribs. Lid  50  is a unitary molded (or vacuumed formed) plastic component that includes a raised rib  51  along side  52  and symmetrically, a second raised rib  53  along the opposite side  54 . The illustrated surface  55  is the outer or upper surface of lid  50  and the “raised” form of the two ribs  51  and  53  refers to extending away from surface  55 . The raised and part cylindrical form of each rib  51  and  53  creates a corresponding part-circular (in lateral cross section) channel  56  and  57 , respectively. Each channel  56  and  57  is constructed and arranged to receive a stiffening member  58  having a shape and material selected from those options already discussed. The edges of ribs  51  and  53  at their junction with the inner face of surface  55  are spaced apart so as to require a snap-fit by the metal tube  58 . 
         [0049]    Raised ribs  51  and  53  (as well as ribs  50   a  and  50   c ) provide some degree of stiffening for the plastic closing lid  50 , depending on the size of the ribs, the wall thickness, the type of plastic being used, the length, etc., even without any stiffening component installed into the defined channel. For added stiffening of lid  50 , each rib  51  and  53  is arranged and is shaped so as to receive a corresponding stiffening member  58 , see  FIG. 12 . Whether the raised form or structure that defines the open channel that receives the stiffening tube (or rod) extends above the upper surface of the lid or below the inner surface, added lid stiffening is provided in substantially the same way. Similar to what has been described relative to the embodiments of  FIGS. 1-10 , each stiffening member  58  can be captured within its corresponding channel  56  and  57  (i.e. the open side of each rib  51  and  53 , respectively) in a variety of ways. One way is to shape each rib and channel such that gap  59  is smaller than the tube diameter so that the tube must be forced into position and thereafter is retained by the shape of each rib and the more narrow gap  59 . Another way to secure the hollow metal tube  58  in the desired position is to use a suitable adhesive. Still another way for securement of the metal tube in position is to insert mold (or form) the hollow metal tube into its corresponding rib. A still further way is to enclose the receiving channel with a cover that can be bonded in place using a suitable adhesive or by ultrasonic welding. 
         [0050]    While the preferred embodiment of the invention has been illustrated and described in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that all changes and modifications that come within the spirit of the invention are desired to be protected.