Abstract:
An adjustable refrigerator shelf assembly receives electrical power through a loosely draped conductor held within a pocket on one side of the shelf assembly. The shelf assembly may include a detent mechanism allowing adjustment of the shelf assembly upward and downward by successive lifting and lowering of the shelf without direct manipulation of a detent or a lock allowing both the detent mechanism and conductor to be wholly covered at all times.

Description:
CROSS REFERENCE TO RELATED CASE 
       [0001]    This application claims the benefit of U.S. provisional application 61/373,410 filed Aug. 13, 2010 hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to refrigerator shelves and in particular to an adjustable refrigerator shelf providing in-shelf lighting. 
       BACKGROUND OF THE INVENTION 
       [0003]    Lights in a refrigerator are typically mounted to the interior walls of the refrigerator compartment. While these lights provide sufficient illumination when the refrigerator is empty, when the shelves are filled with goods, light is blocked and portions of the shelves are cast in shadows. 
         [0004]    One solution to this problem is placement of lighting systems on the shelves themselves, for example on the underside of the shelves to illuminate the contents of the shelf below or on the upper edges of the shelves to illuminate product on the shelf itself. 
         [0005]    A problem with shelf-mounted lighting is getting electrical power to the lights. Refrigerator shelves are typically adjustable in position. While releasable electrical connectors could be provided for connecting electricity to the shelves, these connectors necessarily but undesirably break the continuous inner wall of the refrigerator and expose conductors making cleaning the inner surface of the refrigerator more difficult. 
         [0006]    One solution to this problem is described in PCT patent application WO 2009/079209 having a filing date of Dec. 3, 2008 and entitled “Inductively Powered Light Assembly” assigned to the assignee of the present invention and hereby incorporated by reference. The invention described in this application uses inductively coupled power transfer between a primary coil positioned behind the walls of the refrigerator and corresponding coils on the shelves. An elongated primary coil spanning multiple shelf locations may be used to provide flexibility in the arrangement of the shelves. 
         [0007]    An improvement in this design is described in pending U.S. application 61/314,833 filed Mar. 17, 2010 and entitled “High-Efficiency Wireless Lighting System” which provides a series of separate, smaller coils that provide more focused electrical coupling between power coils in the walls of the refrigerator and corresponding shelf coils on the shelves. Sensing of coil proximity may be used to efficiently disable coils not being used. This application is also assigned to the assignee of the present invention and hereby incorporated by reference. 
         [0008]    It can be difficult to integrate the power coils required for a wireless lighting system into the refrigerator. Mounting the coils behind the refrigerator walls can present manufacturing challenges and the large size of the power transmission coils does not readily integrate into existing shelf brackets. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention combines a shelf mechanism that allows for “blind” adjustment of the shelf between two positions with a flexible continuous conductor providing power to a shelf in either of the two positions. Because the shelf adjustment mechanism does not require access to the mechanism by the user, it may be wholly covered with a shroud that may also isolate and protect the flexible conductor. The present invention eliminates the need to break electrical conductors when the shelves are moved or for more sophisticated wireless energy transmission systems. 
         [0010]    Specifically, the present invention provides an adjustable refrigerator shelf system having a shelf assembly providing a shelf and at least one lamp attached to the shelf assembly for illuminating a region of the shelf. A slide with a first and second slideably connected component has the first component attached to an inner wall of the refrigerator and the second component attached to the shelf assembly. A detent mechanism releasably holds the first and second components at a first and second relative position to locate the shelf assembly at a first and second height in the refrigerator. A shroud is attached to move with the shelf assembly adjacent to the inner wall, the shroud defining at least a portion of an enclosed volume proximate to the inner wall enclosing the detent mechanism. A flexible conductor is held within the enclosed volume providing a conductive path from a point on the inner wall to a point on the shelf assembly, the flexible conductor sized to coil and uncoil within the defined volume as the slide moves between the first and second relative locations. 
         [0011]    It is a feature of at least one embodiment of the invention to provide a simple method of delivering electrical power to an illuminated shelf permitting simple adjustment of the shelf. 
         [0012]    The adjustable refrigerator shelf system may further include a pocket having an opening and attachable to the inner wall with the opening facing inward into the refrigerator, the pocket cooperating with the shroud to define the enclosed volume. 
         [0013]    It is a feature of at least one embodiment of the invention to provide a conductor system that may be wholly enclosed for protection of the conductor from damage or entanglement. 
         [0014]    The shroud may have a vertical height less than a sum of a vertical height of the pocket and a vertical height difference between the first and second relative positions. In addition the shroud may be placed on the outside of the inner wall to communicate with an inside of the refrigerator through an opening in the inner wall having a vertical height less than the vertical height of the shroud to be covered by the shroud in both the first and second positions. 
         [0015]    It is a feature of at least one embodiment of the invention to permit the shroud to cover the enclosed volume holding the conductor in all adjustment positions without unduly increasing the height of the shroud such as may necessitate a larger shelf separation. By partially covering the opening to the pocket, a large pocket size may be obtained with modest shroud sizes. 
         [0016]    The detent mechanism may be an interengaging multi-step track and pin, one attached to the first component and one attached to the second component to permit the second component to stably rest at different heights on the first component in response to successive upward and downward motions of the second component. 
         [0017]    It is a feature of at least one embodiment of the invention to provide an adjustment mechanism that may be wholly contained beneath the shroud to present a surface that is easy to clean. 
         [0018]    The flexible conductor may have a length at least one and one half times a distance of vertical separation between the first and second positions. 
         [0019]    It is a feature of at least one embodiment of the invention to eliminate the need for retractor mechanisms on the flexible conductor by allowing a natural coiling of the conductor facilitated by its excess length. 
         [0020]    The point of attachment of the flexible conductor on the inner wall may be higher than the point of attachment on the shelf bracket at all positions between the first and second position. 
         [0021]    It is a feature of at least one embodiment of the invention to provide a draping of the conductor providing a natural trap for moisture condensation. 
         [0022]    The adjustable refrigerator shelf assembly may include an electrical connector providing a releasable junction in the flexible electrical connector between the first and second points. 
         [0023]    It is a feature of at least one embodiment of the invention to permit simple installation or removal of the shelves for maintenance or assembly. 
         [0024]    The electrical connector may be the first point of attachment of the flexible conductor. 
         [0025]    It is a feature of at least one embodiment of the invention to conduct moisture away from the electrical connector. 
         [0026]    Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]      FIG. 1  is a front perspective view of a shelf assembly for use with the present invention showing a shelf supported against an inner wall of the refrigerator by a shelf bracket, having a shroud covering an adjustment mechanism that may be operated by movement of the shelf without access to the mechanism by the consumer; 
           [0028]      FIG. 2  is an exploded side elevational view of the adjustment mechanism and shroud showing the positioning of a flexible conductor within a cavity in the refrigerator wall; 
           [0029]      FIG. 3  is a front elevational phantom view of a cardioid track formed in the rear surface of the shroud of  FIG. 2  engaging a movable pin to allow blind adjustment of the shelf between the first and second elevation; 
           [0030]      FIG. 4  is cross-sectional elevational view of the assembled shroud and mechanism of  FIG. 2  showing alternative locations for LED illumination of a shelf; 
           [0031]      FIG. 5  is an exploded fragmentary view of an inner wall of the refrigerator showing mounting of a pocket assembly outside of the inner wall for holding the flexible conductor; 
           [0032]      FIGS. 6   a  and  6   b  are elevational views of the opening of  FIG. 5  from just outside of the inner wall looking into the refrigerator showing coiling of the flexible conductor with the shelf in a first and second position; 
           [0033]      FIGS. 7   a  and  7   b  are front and rear perspective views of an alternative shroud design providing for multiple levels of track adjustment. 
       
    
    
       [0034]    Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0035]    Referring now to  FIG. 1 , a refrigerator  10  may provide for a housing  12  having left, right, top, bottom, and rear insulated walls together defining generally an enclosed rectangular volume open at the front. A door  14  may hinge at a front edge of one side wall to provide, when closed, a refrigerated volume maintained at a desired temperature by a compressor system or similar refrigeration system (not shown). 
         [0036]    One or more horizontal, planar shelves  16  may be placed within the volume at various heights as supported by a mechanism  18  on the left and right sides covered by a shroud  20 . The mechanism  18  provides a connection between the shelf  16  and opposed inner walls  22  of the refrigerator  10  allowing the shelf  16  to be raised and lowered between two different heights simply by pressure on the shelf without direct access to the mechanism  18 . 
         [0037]    Referring now to  FIG. 2 , the walls  22  of the refrigerator  10  may include a generally rectangular recessed pocket  26  having at its upper end a pin  28  extending outward therefrom and retained in a horizontal slide track  30  to move horizontally left and right. The pin  28  may engage a cardioid multi-step track  32  facing the pin  28  from a rear surface of the shroud  20  which, as will be described below, cooperates to stably hold the shroud  20  in an upper or lower position. The shroud  20  may be retained slideably against the pocket  26  by a vertical guide mechanism, for example, outwardly extending left and right vertical tracks  34  on the shroud  20  engaging corresponding channels  36  positioned to the left and right of the pocket  26 . This or a variety of other mechanisms may be used to constrain the shroud  20  for vertical travel with respect to the pocket  26 . 
         [0038]    A surface of the shroud exposed to the refrigerator volume may support a shelf bracket  37  holding the shelf  16  and providing illuminators  40 , for example, using light emitting diodes (LEDs) that may illuminate the top of the shelf  16  or, in a different embodiment shown in  FIG. 4 , a bottom of the next lower shelf. Motion of the shroud  20  moves the shelf  16  correspondingly. 
         [0039]    Referring still to  FIG. 2 , a connector  42  within the pocket  26  may attach to a source of power behind the wall  22  to join to a flexible electrical cable  44  that may pass in the pocket  26  to the bottom of the pocket  26  to be loosely coiled (in a zigzag planar form) within the pocket  26  behind the shroud  20 . The lower portion of the pocket  26  may be covered by a portion  50  of the inner wall  22  of the refrigerator as will be described in more detail below. Generally, the term “coil” as used herein contemplates any bundling or folding of the flexible electrical cable  44  into the pocket  26 . 
         [0040]    Referring now to  FIGS. 2 and 3 , the cardioid multi-step track  32  may be a groove extending into the shroud  20  from its rear face and is generally an inverted heart-shape (cardioid) having two lower lobes joining to an upper vertex. The cardioid multi-step track  32  guides the pin  28  as it moves between two stable positions: a lower position (with respect to the shroud  20 ) with the pin  28  at position  46   a  being in a notch between the lobes of the cardioid, and an upper position with the pin at position  46   b  at the uppermost vertex of the cardioid multi-step track  32 . The upper position of the pin  28  represents the lowest position of the shelf  16  and vice versa. Starting with the shroud  20  at its lower position where the pin  28  is at upper position  46   b  on the shroud  20 , the cardioid multi-step track  32  is generally asymmetric so that the pin  28 , starting at position  46   b  and moving downward with respect to the shroud  20  with a lifting of the shelf  16  and shroud  20 , will follow a leftmost groove of the cardioid multi-step track  32  to a position  46   c  in the leftmost lobe of the cardioid multi-step track  32  where the pin  28  is trapped against further relative downward motion. 
         [0041]    Downward motion of the shelf  16  and shroud  20  from position  46   c  requires the pin  28  to rise to position  46   a  where it supports the cardioid multi-step track  32  to hold the shelf  16  in a second position elevated with respect to the shelf position when the pin  28  was at position  46   b  where it started. 
         [0042]    New, upward motion on the shelf  16  and shroud  20  causes the pin  28  to move downward relative to the shroud  20  to position  46   d  in the rightmost lobe of the cardioid multi-step track  32  where subsequent upward motion of the pin  28  from this position (by downward motion of the shroud  20 ) causes it to return to position  46   b.    
         [0043]    Thus, successive upward and downward motion on the shelf  16  (and hence shroud  20 ) by the consumer moves the shelf  16  bi-stably between upper and lower positions. As the pin  28  moves through the cardioid track, it may slide within slide track  30  slightly to accommodate left and right movement of the pin  28  necessary to follow the cardioid multi-step track  32 . A cardioid track of similar design is described generally in European patent EP 1563762 filed Feb. 16, 2005 and entitled: “Easy Height Adjustment Device for Refrigerator Shelves” assigned to the assignee of the present invention and hereby incorporated by reference. 
         [0044]    It will be understood that the relative positions of the cardioid multi-step track  32  and the pin  28  may be reversed to provide for a similar mechanism with the cardioid track inverted. 
         [0045]    Referring now to  FIG. 4 , the cable  44  may connect to a printed circuit board  56  and/or printed circuit board  58  held in the shelf bracket  37  after passing through an entry point  49  in the shelf bracket  37 , the cable  44  providing power to one or more LEDs  40  contained in a compartment  60  or  62  of the shelf bracket  37  behind a transparent or translucent window  64  or  66 . 
         [0046]    The shelf  16  may be a plate of tempered glass so that light from the LEDs  40  on top of the shelf  16  may illuminate the shelf  16  and some light may pass through the shelf  16  to illuminate a lower shelf. Conversely, light from LED  40  below the shelf  16  may illuminate the next shelf below and by reflection through the shelf above. 
         [0047]    Referring now to  FIG. 5 , the pocket  26  may be a separate assembly  68  providing a shallow tray opening on one face. The assembly  68  may be attached to the inner wall  22  from outside the inner wall  22  so that an open face of the pocket  26  is exposed through an opening  70  cut in the inner wall  22 . The opening  70  in the inner wall  22  may be smaller in vertical height than a vertical height of the pocket  26 , thus minimizing the breach through the refrigerator wall  22 . The assembly  68  may support the pin  28  and hold the connector  42  and cable  44 . 
         [0048]    Referring also to  FIGS. 6   a  and  6   b , a vertical height  72  of the opening  70  in one embodiment will be no greater than the vertical height  74  of the shroud  20  (shown in  FIG. 3 ) minus the vertical separation  76  between the two positions of the shelf  16  in its stable resting states as defined by the cardioid multi-step track  32  (shown in  FIG. 3 ). In this way, the vertical height  74  of the shroud  20  may be minimized while still covering the opening  70  when the shelf  16  is both in its lowermost position (shown in  FIG. 6   a ) and in its uppermost position (shown in  FIG. 6   b ). This smaller opening  70  permits a smaller shroud  20  in turn permitting closer spacing of the shelves  16  in the refrigerator  10 . More generally, the shroud  20  can be constrained to have a vertical height  74  that is less than the sum of the vertical height  75  of the opening of the pocket  26  and the vertical separation  76  of the shelf positions. A shroud  20  having a height equal to this sum would be required if the opening  70  had the same height as the pocket  26 . This ability to thus increase size the pocket  26  while keeping it covered by the shroud  20  permits a reduced bending of the cable  44  and allows the weight of the cable  44  to provide a natural retraction of the cable  44  into the pocket  26  without retraction mechanisms or the like. 
         [0049]    When the shelf  16  is in its lowermost position, the cable  44  may coil behind a portion  50  of inner wall  22  whereas when the shelf  16  is in its uppermost position the cable  44  may yet drape in a single loop downward from the connector  42 . In all cases, the connector  42  will be higher than the shelf and an entry point  49  in the shelf bracket  37 . 
         [0050]    Referring now to  FIGS. 7   a  and  7   b , in an alternative design, more than two different heights of shelf adjustment may be obtained by a brachiated multi-step track  32 ′ operating according to a similar principle as the cardioid multi-step track  32  described above, but having more than two stable resting positions. Specifically the brachiated multi-step track  32 ′ provides six stable resting positions  78   a - 78   e  at which the pin  28  may support the shroud  20 . In particular, this design provides four different levels  80   a - 80   d  (from highest to lowest on the shroud  20 ) at which the shroud  20  and hence the shelf (not shown in  FIG. 7 ) may be positioned stably by sequential upward and downward movement of the shroud  20  with respect to the refrigerator wall  22 . 
         [0051]    During the adjustment process, the pin  28  may move from the highest resting position  78   a  at level  80   a  (lowest shelf position), then with upward then downward motion to resting position  78   b  at level  80   b , and similarly and subsequently to resting position  78   c  at level  80   c  and then to resting position  78   d  at level  80   d . Continued upward then downward motion may then cycle the pin  28  upward, first to resting position  78   e  at level  80   c , and then to resting position  70   f  at level  80   b , and finally again to resting position  78   a . It will be appreciated, from these two examples of the cardioid multi-step track  32  and the brachiated multi-step track  32 ′, which arbitrary numbers of levels  80  may be provided including different numbers of levels when moving the shelf up as opposed to when moving the shelf down, with the same shroud  20 . 
         [0052]    The embodiments of  FIGS. 7   a  and  7   b  also depict an alternative method of attaching the shroud  20  to the wall  22  of the refrigerator  10  by using a wall-mounted panel  82  that may be attached to the inner surface of the wall  22 , for example, by self tapping screws (not shown) and mounting holes  84  in the panel  82 . The wall-mounted panel  82  may support on its rear surface (with respect to the interior of the refrigerator  10 ) a separate component  86  providing for the pocket  26 , such component  86  as may fit through a hole in the wall  22  or be contained entirely in the thickness of the wall mounted panel  82 . In this embodiment, the vertical tracks  34  may most readily be placed on the wall-mounted panel  82  and the corresponding channels  36  placed on the shroud  20 . A separate connector  42 ′ may attach the cable  44  (which may be a flat cable) to the printed circuit card  56 . 
         [0053]    Various features of the invention are set forth in the following claims. It should be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth herein. The invention is capable of other embodiments and of being practiced or carried out in various ways. Variations and modifications of the foregoing are within the scope of the present invention. It also being understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.