Abstract:
A rack for holding specimen slides. The rack has a frame with opposed support bars having opposed openings for supporting opposite ends of the specimen slides. The support bars have edges connected to sides of the frame, so that the support bars are resiliently deflectable with respect to the frame. The rack of specimen slides is containable in a slide case for purposes of transportation. The slide case has a base with a first latch portion, and the rack has a second latch portion. As the rack is positioned adjacent the base, the first and second latch portions are placed in juxtaposition to releasably secure the rack in the base. A cover is positionable over the base such that the base and cover fully enclose the rack of specimen slides. As the cover is closed over the base, the cover pushes the specimen slides against the opposed support bars, thereby deflecting the support bars and securing the specimen slides in the slide case.

Description:
FIELD OF THE INVENTION 
     This invention relates generally to a container for storing specimen slides and, more particularly, to an improved container for storing and transporting specimen slides. 
     BACKGROUND OF THE INVENTION 
     There are known storage containers for the bulk storage of frangible sheet material, such as specimen slides. Known containers often have opposed pairs of slots separated by a fixed distance for receiving the slides, and such storage containers have proven satisfactory for storing slides. However, the slides are often subjected to various processes, for example, dipping in liquids and preprocess drying in a centrifuge, but the known storage containers are not suitable for use in such processing. Therefore, the slides must be removed from the storage containers and transferred to other racks that can be used with the preprocessing machines. 
     In other situations, the slides must be shipped to another location. Known bulk storage containers are not able to protect the slides from the rigors of commercial shipping and transportation that are widely used to ship other items. Therefore, the slides must be removed from the bulk storage container and repackaged for shipment. Such special handling is not cost effective in most commercial environments. Thus, the repeated handling of each individual slide required by known bulk storage containers adds substantial cost to processes to which the slide is subjected. 
     Consequently, there is a need for a bulk storage container that overcomes the disadvantages of known slide storage containers discussed above. 
     SUMMARY OF THE INVENTION 
     The present invention provides a slide storage system that is simple in construction, flexible and durable in use. The slide storage system of the present invention secures the slides so that they do not chip in their supports, and the storage system is sufficiently durable that it can be used to transport the slides. Further, the storage system has a structure permitting slides to be processed while contained within the storage system. Thus, by substantially reducing the need and associated costs of removing and reloading the slides, the slide storage system of the present invention is especially useful in environments where slides are subjected to preprocessing and/or where the slides must be transported to another location. 
     According to the principles of the present invention and in accordance with the described embodiments, the invention provides a rack for holding specimen slides. The rack has a frame with a first support bar having an opening adapted to support one end of a specimen slide. The first support bar has a first edge connected to a first side of the frame, so that the first support bar is movable with respect to the frame. 
     In one aspect of this invention, the rack has a second support bar disposed in the frame substantially parallel to the first support bar. The second support bar has an opening for supporting an opposite end of the specimen slide and a first edge connected to an opposite side of the frame, so that the second support bar is movable with respect to the frame. 
     In another embodiment of the invention, a slide case is provided for holding and transporting specimen slides. The slide case has a base having a first latch portion and a rack positionable adjacent the base with a second latch portion. As the rack is positioned adjacent the base, the first and second latch portions are placed in juxtaposition to releasably secure the rack in the base. A cover is positionable over the base such that the base and cover fully enclose the rack. 
     In one aspect of this invention, one of the first and second latch portions is a projecting detent and the other latch portion is a recess. The latch being formed by the projecting detent being captured in the recess. In another embodiment of this invention, the cover has a rib that engages upper edges of the slides upon the cover being placed on the base. As the cover is fully engaged, the slides are pushed against a cantilevered support to slightly deflect the support and securely capture or clamp the specimen slides within the slide case. So secured, the case of specimen slides may then be shipped using commercial carriers without breaking or chipping the specimen slides. 
     In another embodiment of the invention, a method is provided for inserting specimen slides into opposed supports, one of the supports having one edge attached to, and being movable with respect to, one side of a rack. Next, the rack holding the specimen slides is inserted into a base; and a cover is placed over the base so that the cover contacts upper edges of the specimen slides. As the cover is further moved toward the base, the cover simultaneously pushes the specimen slides against the one of the supports so that the one of the supports deflects, thereby securing the specimen slides in the slide case between the cover and the one of the supports. 
     These and other objects and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a disassembled perspective view of a slide case in accordance with the principles of the present invention. 
         FIG. 2  is perspective view of a slide rack used with the slide case of  FIG. 1 . 
         FIG. 3  is a cross-sectional view taken along line  3 — 3  of  FIG. 2  and illustrates an end view of the slide rack. 
         FIG. 4  is a top plan view of the slide rack of  FIG. 2 . 
         FIG. 5  is a cross-sectional end view of the assembled slide case of  FIG. 1 . 
         FIG. 6  is a centerline cross-sectional view of an end of the assembled slide case that illustrates the slide rack latch. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1 , a slide case  20  is comprised of a lower case or base  22  that removably receives and supports a slide rack  24 . The rack  24  individually supports and stores a plurality of flat, planar, rectangular slides  26 , for example, glass specimen slides often used in laboratories. To facilitate picking up and carrying the rack  24 , the rack  24  has handles  79  formed by upward extending tabs  80  and holes  81 . An upper case or cover  28  fits over the slide rack  24  and when secured, abuts against the base  22 , thereby providing the enclosed slide case  20 . Referring to  FIG. 2 , the rack  24  has a quadrilateral frame  30  with two opposed longitudinally extending side walls  32  and opposed end walls  34 . The rack  24  has no bottom or lower wall, and thus, fluids are able to pass through the rack  24 . Two opposed support bars  36  are rigidly connected to the sides  32 . The support bars  36  have a series of generally diamond shaped openings  38 , and each of the openings  38  provides a subjacent support at one end of a lower edge  25  of a slide  26  shown in phantom. The diamond shape of the openings  38  minimizes contact between the slides  26  and the support bars  36 . 
     Referring to  FIGS. 3 and 4 , each of the support bars  36  has an upper edge  40  that is rigidly connected to an inside surface  42  of the rack sides  32 . However, the ends  41  of the support bars  36  do not extend to or contact the end walls  34 , so that there is a small space  43  between the support bar ends  41  and the rack end walls  34 . Thus, the support bar upper edge  40  is the only connection of the support bar  36  to the rack  24 ; and hence, the support bars  36  are cantilevered from the side walls  32 . The support bars  36  extend angularly inward and downward from respective side wall inside surfaces  42  toward a bottom edge  48  of the side walls  32 . Further, each of the support bars  36  is movable or resiliently deflectable in response to a downward force to a distal end  46  of a respective support bar  36 . 
     The ends  34  of the rack  24  have a greater height than the sides  32 ; and therefore, the lower edges  44  of the ends  34  extend below the lower edges  48  of the sides  32 . Thus, an opening or space  50  is provided over a length of the sides  32  between the side lower edge  48  and a plane defined by the lower edges  44  of the ends  34 . 
     Referring to  FIG. 1 , the base  22  and cover  28  are substantially identical in construction. The base  22  and cover  28  may have different labeling either molded in or applied thereto. Each of the base  22  and the cover  28  has a major containment wall  55  with side walls  56  and end walls  58  extending around a periphery of the wall  55 , thereby defining a cavity  61 . Further, each of the base  22  and cover  28  has a pair of spaced apart ribs  54  disposed on an inner surface  57  within the cavity  61 . The ribs  54  extend lengthwise in a direction substantially parallel to the sides  56  and substantially perpendicular to the ends  58 ; and therefore, when a rack  24  of slides  26  is mounted in the case  20 , the ribs  54  are substantially perpendicular to planes of the slides  26 . Further, each of the base  22  and cover  28  has a first latch portion  60 , for example, a projection or detent, extending inwardly from an inner surface  62  of each of the end walls  58 . The rack  24  has a second latch portion  64 , for example, a dimple or recess, disposed on an outer surface  66  of each of the end walls  34 . 
     The rack ends  34  have arched openings or notches  68  that reduce their stiffness and provide the rack ends  34  with some resiliency. Therefore, as the rack  24  is placed into the base  22 , the rack ends  34  and/or the base ends  58  deflect slightly so that projections  60  ride over respective rack end surfaces  66  until the projections  60  snap into respective recesses  64 . With the projections  60  disposed in the recesses  64  as shown in  FIG. 6 , the rack  24  is now securely mounted in, and partially enclosed by, the base  22 . There is sufficient clearance  65  between the ends of the ribs  54  and the rack ends  34  so that the lower edges  44  of the rack ends  34  rest directly on the inner surface  57  of the base wall  55 . Each rack end  34  has a lower edge segment  69  that is slightly beveled downward and inward from an end wall outer surface  66  to a lower edge  44 , so that the first latch portion or detent  60  more readily slides over the outer surface  66  toward the second latch portion or recess  64 . 
     With the rack  24  mounted in the base  22 , the cover  28  is aligned with the base  22  and placed over the rack  24  and slides  26 . The cover  28  is moved toward the base  22  while maintaining its alignment with the base  22 . Referring to  FIG. 5 , as a lower peripheral edge  74  of the cover  28  approaches, but before it contacts, an upper peripheral edge  76  of the base  22 , the ribs  54  on a cover inner surface  59  contact upper edges  78  of the slides  26 . In this embodiment, when the cover lower edge  74  is approximately 0.005 inches from the base upper edge  76 , the ribs  54  contact the slide upper edges  78 . As the cover  28  is further moved toward the base  22 , the force of the ribs  54  contacting the slide upper edges  78  causes the resiliently cantilevered support bars  36  to deflect slightly downward toward the lower edge  48  of the rack side walls  32 . The cover  28  is further moved until the cover lower edge  74  contacts the base upper edge  76 , thereby limiting the force applied to the slide upper edges  78  and the deflection of the support bars  36 . With the cover  28  fully closed on the base  22 , the slides  26  are clamped or secured between the cover ribs  54  and the support bars  36  of the rack  24 . 
     When the cover  28  is moved away from the base  22 , the cover ribs  54  lose contact with the slide upper edges  78 ; and the support bars  36  move away from the lower edge  48  of the rack side walls  32  and return to their original, unloaded and undeflected position. The rack  24  can be removed from the base  22  by either, direct manual manipulation or, a carrier can be inserted into the holes  81  and used to lift the rack  24  from the base  22 . To remove the rack  24  from the base  22 , the upper extending tabs  80  ( FIG. 1 ) on the rack ends  34  are pressed inward toward each other. The size of notches  68  determines the force necessary to slightly warp or bend the rack ends  34 . The tabs  80  are pressed inward until the lower edges  70  of respective recesses  64  are clear of respective projections  60 , and the rack  24  is moved out of the base  22 . In that process, the lower edges  70  of the recesses  64  move past the latch projections  60  on the base  22 , thereby unlatching the rack  24  from the base  22 . It should be noted that the base  22  and cover  28  serve different functions, but they are substantially identical in construction. Therefore, as will be appreciated from the above description, the ribs  54  on the base  22  and the first latch portion  60  of the cover  28  ( FIG. 1 ) serve no purpose. 
     The base  22 , rack  24  and cover  28  are normally molded from a high density polyethylene material. However, as will be appreciated, those parts may be made of polypropylene, polycarbonate or any other plastic material that does not outgas. As will be appreciated, the parts can be made of other materials that are suitable for the intended use. The base  22 , rack  24  and cover  28  are often made to be opaque in order to protect the slides from the adverse effects of light, if any. 
     In use, the supplier of the slides cuts the slides to the desired size, and cleans and dries them. Often, the glass slides are used as specimen slides to hold and/or store samples of DNA. In those applications, the supplier of the glass slides may coat the specimen slides in a liquid or vapor deposition process in which a DNA binding chemical provides the desired coating. The specimen slides  26  are loaded in the rack  24 ; and using the handles  79 , the rack  24  is placed in a base  22 . The latching members  60 ,  64  secure the rack  24  in the base  22  as previously described. Next, the cover  28  is placed on the base  22  and the case  20  filled with slides  26  is vacuum sealed in a barrier bag, for example, an aluminum foil bag, so that the cover  28  is held firmly against the base  22 . With the cover  28  firmly closed against the base  22 , the slides  26  are clamped within the case  20 ; and the sealed case with the slides may be shipped to a customer using known commercial carriers. 
     When received by a customer, for example, a DNA laboratory, the vacuum package is opened and the cover  28  is removed. The rack  24  with the slides  26  may then be removed from the base by depressing the ends  34  to release the latch members  60 ,  64 . Either, the handles  79  or a carrier (not shown) inserted into the handle holes  81 , is used to pull the rack  24  from the base  22  and carry the rack  24  from one location to another. It should be noted that there are numerous procedures for processing the slides in the rack  24 . The following are only a few examples of the processing options. If desired, the customer is able to preprocess the specimen slides while still in the rack  24 . In this example, the rack  24  with the specimen slides  26  is dipped in one or more liquids. Thereafter, the excess liquid is removed in a centrifuge. Prior to being placed in the centrifuge, the rack  24  is reinserted in a base  22 . The base may be the same one that was used to ship the rack  24 . Alternatively, it may be desirable to keep that base clean, and a different base can be used to hold the rack while in the centrifuge. After drying, the slides are often removed from the rack and placed in other equipment to be spotted, hybridized and scanned. If at any time during those processes, it is necessary to store the slides, they can again be placed in the rack  24 . The rack is than placed in the base  22 , and the cover  28  is placed on the base  22  to form a closed case  20 . As will be appreciated, the cover  28  can be temporarily secured on the base by a surrounding tie or band, or the case can again be placed in a vacuum sealed package. The case can also be placed in the barrier bag in which it was received by the customer. 
     The slide case  20  has a structure permitting slides to be preprocessed while contained within the rack  24 . Further, when the cover  28  is applied over the base  22 , the slides  26  are immobilized in the slide case  20 . That immobilization in combination with the durability of the slide case  20  make it a suitable container for transporting the slides using commercial carriers. Thus, by substantially reducing the need and associated costs of removing and reloading the slides, the slide case  20  with the rack  24  is especially useful in environments where slides are subjected to preprocessing and/or where the slides must be transported to another location. As will be appreciated, the ability to process batches of slides in a rack  24  by the slide supplier as well as the customer, represents a substantial opportunity for cost savings. Further, the substantially identical structure of the base  22  and cover  28  permits both parts to be made from a single mold, thereby substantially reducing the cost of the molds needed to manufacture the case  20 . 
     While the invention has been illustrated by the description of one embodiment and while the embodiment has been described in considerable detail, there is no intention to restrict nor in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those who are skilled in the art. For example, in the described embodiment, the ribs  54  contact the slide upper edges  78  with an about 0.005 inch spacing between the cover lower edge  74  and the base upper edge  76 . As will be appreciated, the spacing may vary depending on the size of the slides  26  and the case  20 , the resiliency of the support bars  36 , the desired securing force to be applied to the slide top edges  78 , etc. 
     In the described embodiment, the ribs  54  are shown as being of a continuous length and substantially parallel to the sides  32 . However, as will be appreciated, in an alternative embodiment, the ribs may take the form of any shaped projections that are positioned so that they contact the slide upper edges. Further, the ribs  54  or other projections can be continuous or discontinuous and oriented in any direction on the wall  55  of the cover  28 , for example, the ribs can extend diagonally from corner to corner. In addition, while two ribs  54  are shown, in an alternative embodiment, only one rib can be used. In a still further embodiment, the ribs  54  can be eliminated and the inside surface of the wall  55  of the cover  28  used to contact the slide upper edges  78 . 
     In the described embodiment, the latch between the rack  24  and the base  22  is comprised of a projection on the base end wall  58  and a recess on the rack end wall  34 . As will be appreciated, in an alternative embodiment, the location of those parts can be reversed with the projection being on the rack end wall  34  and the recess being on the base end wall  58 . In other embodiments, other latch mechanisms may be used, for example, the base may have a resilient finger that extends over an upper edge  76  of the rack end walls  34 . While a latch is shown at the ends of the rack  24 , in alternative embodiments, one or more latches may be operative with the rack sides  32  or a combination of the rack ends and sides. In further embodiments, fewer or more than two latches may be used to secure the rack  24  in the base  22 . 
     In the described embodiment, the sides  32  have a lesser height than the ends  34 ; and thus, a passage or space  50  for fluid drainage exists beneath the sides  32 . As will be appreciated, in alternative embodiments, the space  50  may be provided under only one of the sides walls  32  or under one or both of the end walls  34 . 
     In addition, while the illustrated embodiment shows a case of a particular size for a particular number of slides; as will be appreciated, the claimed invention is applicable to a case of any size for any number of slides. Further, in the illustrated embodiment, both of the support bars  36  are described as being cantilevered from a side wall  32  by having only one edge connected to the side wall. Further, the diamond shaped openings in the support bars  36  may be replaced by any shaped hole or opening that supports the slides  26  in a desired manner. 
     As will be appreciated, in an alternative embodiment, only a single movable support bar  36  can be used to support one end of the specimen slide and a fixed support is used to support the opposite end of the specimen slide. The fixed support can be a fixed support bar or other fixed supports such as V-shaped notches or slots molded on the inside surface of a rack side  32 . With this embodiment, it may be desirable to mount the fixed support at a slightly lower elevation on a rack side wall  32 , such that when the slide is mounted in the rack and the cover is on the base, thereby deflecting the movable support bar, the slide is squarely supported with respect to the case. 
     Therefore, the invention in its broadest aspects is not limited to the specific details shown and described. Consequently, departures may be made from the details described herein without departing from the spirit and scope of the claims which follow.