Patent Publication Number: US-6658903-B1

Title: Thermally insulated lock box and lock therefor

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     The present invention is directed to a lock box that is thermally insulated to permit medical samples, and the like, to be securely and safely stored for pickup for periods of 8 hours and more. More particularly, the present invention is directed to a lock box equipped with a failsafe lock which will not permit the key to be removed unless the lock elements are securely engaged. 
     Medical storage boxes have been produced by the assignee of the present invention, and others, for some time. These boxes are used for storing medical samples (blood, urine, etc.) for limited periods of time outside the offices to provide a courier from an analysis lab, for example, after-hour access to pick up the samples. Legislation approved by the California Senate (Senate Bill #765) requires reporting of any incidents of unlocked specimen boxes. It is therefore desirable to provide a failsafe lock mechanism in which the key cannot be removed from the lock unless the lock elements are properly engaged. In addition, it is desirable to provide a lock box which can store frozen samples for periods of 16 hours at temperatures below 30° F., as low as 5° F. Lastly, the styrene (or styrofoam) insulation used to line the lock box is subject to abuse as a result of insertion and removal of the stored items. It is therefore desirable to provide a separable liner which can be removed and replaced should the inner liner become worn, soiled or damaged. 
     The present invention addresses these concerns by providing a storage box for heat-sensitive sample containers comprising a generally rectangular enclosure defined by an outer peripheral wall of rigid material, said enclosure having four lateral walls, a bottom wall and a top wall which is pivotally attached to one of said four lateral walls; at least one layer of insulation lining an inner portion of each of said four lateral walls, said bottom wall and said top wall; a fail-safe, key-operated lock having a first member associated with said top wall and a second member associated with a second one of said lateral walls, said lock precluding a key from being removed from said lock unless said first member and said second member are in interlocking engagement; whereby said sample containers may be locked in said storage box with at least one freezable packet, said insulation having sufficient thickness to maintain a temperature of the heat-sensitive sample containers below a desired maximum temperature for at least eight hours regardless of an ambient temperature surrounding said box. The rigid material making up the outer peripheral wall is preferably sheet metal that is coated with a protective coating such as an enamel paint. Further, it is preferred that the box has adequate interior volume to accommodate at least one soft-sided, insulated satchel that can be removed with their refrigerated contents. The innermost liner of styrene is held in by a fiction fit and may be easily removed and replaced in the event of wear, soiling or damage. 
     The failsafe lock preferably comprises a cam cylinder associated with a first one of said top wall and said second lateral wall, said cam cylinder having a first latching means attached thereto and being operable by said key, said cam cylinder being oscillatable by said key between a first latched position and a second unlatched position; a second latch means associated with another of said top wall and said second lateral wall; a spring associated with the same one of said top wall and said second lateral wall as said cam cylinder and engaging a portion of said cam cylinder disabling its rotation to a position where said key could be removed therefrom; a push bar associated with said another one of said top wall and said second lateral wall for engaging said spring and moving it to a non-disabling position when said second latch means is positioned where it can be engaged by said first latch means; whereby said cam cylinder can only be rotated to a key-removable position when said top wall is closed so that said second latch means can be engaged by said first latch means. While this lock has been designed for use with a medical sample lock box, it will have general utility with other applications where it is desirable to ensure securement of a lock prior to withdrawal of a key. 
     Various other features, advantages and characteristics of the present invention will become apparent to one of ordinary skill in the art after a reading of the following specification. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The preferred embodiment(s) of the present invention is/are described in conjunction with the associated drawings in which like features are indicated with like reference numerals and in which 
     FIG. 1 is a side view of a first embodiment of the lock box of the present invention; 
     FIG. 2 is a front view of the first embodiment with the lid removed for clarity; 
     FIG. 3A is an enlarged top view of the locking mechanism of the present invention; 
     FIG. 3B is an enlarged front view of the locking mechanism of the present invention; 
     FIG. 3C is an enlarged side view of the locking mechanism of the present invention; 
     FIG. 4 is an exploded perspective view showing an exemplary carrier used with the lock box of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A first embodiment of the thermally insulated lock box for storing medical samples, and the like, is shown in FIG. 1 generally at  20 . Lock box  20  comprises a generally rectangular enclosure  22  made of rigid material and having four lateral walls  24 , a bottom wall  26  and a top wall formed by lid  28  which is pivotally attached to one of the lateral walls  24 . Lid  28  is pivotally attached to a first lateral wall  24  to allow it to be raised to provide access to the enclosure  22 . The rigid material is preferably sheet metal with each of the peripheral walls  24 ,  26 ,  28  having at least one layer  30  of thermal insulation. In fact, it is preferred that a second layer of insulation which may be styrene form an internal separable layer  32  retained by a friction fit and that can be removed and replaced in the event that it becomes worn, soiled or damaged. 
     As shown, lock box  20  can accommodate two removable carriers  11  (FIG.  4 ). Carriers  11  are preferably soft-sided coolers commercially available from a number of sources. Each carrier  11  has a shoulder strap  13  to enable ease of grasping and transport. Carrier  11  can be equipped with two freezable cooler packs  15  that can sandwich two medical vial securement boxes  17 . Cooler packs  15  may alternatively be of a commercially available type capable of maintaining medical samples below 30° for extended periods up to  16  hours or of a second type capable of maintaining the samples below 5° for up to 16 hours. Each box  17  has a bottom  19  with a plurality of recesses  21  to receive conventional medical vials (not shown) and a top  23 . Typically, the samples will be pre-frozen for transport and the box  17  will provide a limited amount of thermal insulation in addition to providing protection against jostling. Lock boxes  20  are also available in a single width version where sample volume does not warrant the larger box. 
     All exposed surfaces of enclosure  22  are preferably coated with a baked on enamel paint. This coating  34  will protect the surface of the enclosure  22 , providing an attractive exterior, and will reflect a portion of the ultraviolet radiation striking the box  20  reducing the amount of thermal insulation needed to maintain a preferred maximum temperature within the enclosure  22 . A layer of foil may also be used to line the interior of the box to reflect some of the ultraviolet radiation to avoid its penetration into the interior of enclosure  22 . 
     The failsafe lock device is best shown in FIGS. 3A-3C generally at  40 . Fail-safe, key-operated lock comprises a cam cylinder  42  associated with a first one of the lid  28  and the second lateral wall  24 . The cam cylinder  42  has a first latching means  44  attached thereto, the latching means  44  being operable by a key inserted into key slot  45  to rotate at least a portion of cam cylinder  42  between a first latched position and a second unlatched position. A second latch means  46  is associated with the other of the lid  28  and the second lateral wall  24 . A leaf spring  48  associated with the first one of the lid  28  and the second lateral wall  24  (i.e., the same one as the cam cylinder) and engaging a portion  50  of the cam cylinder disabling its rotation to a position where said key  54  could be removed therefrom. 
     A push bar  52  associated with the second one of the lid  28  and the second lateral wall  24  for engaging spring  48  and moving it to a non-disabling position when the second latch means  46  is positioned where it can be engaged by the first latch means  44  securing the lid  28  in the closed position. In the embodiment shown in the figures, the push bar  52  and second latch means  46  are associated with lid  28  and cam cylinder  42  with first latch means  44  is associated with lateral wall and, are mounted beneath a inwardly directed flange  56 . An oblong slot  58  permits push bar  52  access to leaf spring  48  to move it to a non-disabling position. Accordingly, the key  54  cannot be removed from the lock unless the lid  28  is latched shut. This will protect medical samples from possible tampering or unauthorized removal. 
     Various changes, alternatives and modifications will become apparent to one of ordinary skill in the art following a reading of the foregoing specification. It is intended that any such changes, alternatives and modifications as fall within the scope of the appended claims be considered part of the present invention.