Patent Publication Number: US-2007096610-A1

Title: Retractable shelf for the cabinet of a refrigeration appliance

Description:
FIELD OF THE INVENTION  
      The present invention refers to a retractable shelf to be used inside the cabinets of refrigeration appliances, such as refrigerators, for allowing the user to selectively displace the shelf between at least one lower operative position and a retracted upper operative position.  
     PRIOR ART  
      The shelves used inside the cabinets of refrigerators and freezers are generally defined by horizontal panels constructed in different materials and which are laterally seated on supports provided on the internal lateral walls of the cabinet.  
      In many of the known constructive solutions, the cabinets are laterally provided with different levels of internal supports, so as to allow the shelves to have their vertical positioning adjusted, as a function of the products to be refrigerated in the interior of the cabinet.  
      While the known height adjusting systems give certain flexibility to the user regarding the assembly of the shelves as a function of each standard of use of the refrigeration appliance, there are situations in which the known height adjustments do not comply with the user&#39;s needs, which can last few hours or some days.  
      In some cases, in which the need of having a larger free gap available between two shelves is restricted to only a certain area, such as the frontmost region of the shelves, there is no need for a larger free height in the rear region. In these cases, the known constructions, in which each shelf is defined in a single panel, require the user to remove one of the shelves from the cabinet to obtain the necessary free gap, even if the need for a larger height between both shelves is only directed to a reduced surface area of these parts that form a refrigerating cabinet.  
      There are known from the art the shelves with a reduced depth, which allow the user to obtain a larger vertical free gap in the front region of the whole shelf disposed immediately below the narrower shelf. However, this construction unnecessarily reduces the total support area of the shelves when there is not a momentary or constant need for the larger partial free gap, which is obtained by using a narrower shelf.  
      Furthermore, if a larger vertical free gap over the total area of a shelf is needed, even the narrower shelf has to be removed from the interior of the cabinet. The temporary removal of one or more shelves is uncomfortable for the user, besides producing an additional component which has to be adequately stored during the time of the operational condition that caused its removal.  
      Another known construction is described in Brazilian patent BR PI0104847-3 and comprises a shelf formed by two superiorly coplanar flat frames, one being the front frame and the other the rear frame, the front frame being displaced between a whole shelf position and a reduced shelf position, in which both frames in an overlapped condition can be angularly displaced upwardly backwardly to a vertical retracted position, in which they remain seated or adjacent to the internal rear wall of the cabinet.  
      While leading to a great operational versatility, allowing the shelf to have its depth varying from a maximum value to a reduced value, usually about half the maximum depth, and from this reduced value to a null value, this construction is complex and expensive, making its application difficult and restrictive.  
      Documents U.S. Pat. No. 4,528,825 and JP 2000371013 disclose a retractable shelf, which is maintained laterally suspended by two pairs of arms (larger or smaller) in a parallelogramic arrangement. The shelf can be thus displaced between at least one lower operative position, disposed below the plane of articulation of the arms to the cabinet, and an upper operative position, in which the shelf is conducted to a position generally adjacent to a shelf or a wall immediately above the cabinet.  
      These prior constructions require the assembly of suspending elements hinged to the internal lateral walls of the cabinet, which also conducts to complex and expensive constructions, limiting the use thereof.  
     OBJECTS OF THE INVENTION  
      It is a generic object of the present invention to provide a retractable shelf for the cabinet of a refrigeration appliance, presenting a simple construction with a relatively low cost and which allows, through an easy and fast operation, the shelf to be manually displaced between at least one lower operative position, defining a storage free gap in relation to a shelf or a dividing wall disposed immediately above, and an upper operative position, in which it is conducted to be positioned in a higher level, reducing or anullating the height of said storage free gap defined above said retractable shelf.  
     SUMMARY OF THE INVENTION  
      This and other objects are attained through a shelf for the cabinet of a refrigeration appliance, such as a refrigerator or freezer, said shelf having each lateral edge slidingly mounted, by two longitudinally spaced apart seating regions, on respective rail portions affixed to opposite internal lateral walls of the cabinet, in order to be selectively displaced between at least one lower operative position and one transitional intermediary position, in which it is upwardly and forwardly displaced, and also between said transitional operative position and an upper operative position, in which it is backwardly displaced, situated above and vertically spaced from the lower operative position.  
      The construction of the rail portions is made so that the shelf is displaced from the lower operative position to the upper operative position, when it is forwardly pulled by the user, until reaching the transitional intermediary position, and then backwardly pushed to the upper operative position. The displacement of the shelf back to the lower operative position is accomplished by movements which are inverted in relation to those described above. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The invention will be described below, with reference to the enclosed drawings, given by way of example of a preferred embodiment and in which:  
       FIG. 1  is an upper perspective view of the present shelf mounted on the respective rail portions and which is illustrated in the lower operative position;  
       FIG. 2  is a front elevational view of the assembly illustrated in  FIG. 1 ;  
       FIG. 3  is a perspective view similar to that of  FIG. 1 , but illustrating the shelf in the upper operative position;  
       FIG. 4  is a front elevational view of the assembly illustrated in  FIG. 3 ;  
       FIG. 5  is an internal lateral view of two rail portions constructed in a single piece to be mounted on each of the opposite internal lateral walls of the cabinet;  
       FIG. 6  is an exploded front perspective view, illustrating part of the internal rear wall and part of one of the internal lateral walls of a cabinet, as well as the two respective rail portions, as defined in  FIG. 3 ; and  
       FIG. 7  is a view similar to that of  FIG. 6 , but illustrating the two rail portions already mounted to the respective internal lateral wall of the cabinet. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      As illustrated and previously mentioned, the present shelf is of the type used in the interior of a cabinet  10  of refrigeration appliances, particularly refrigerators, said cabinet  10  comprising, in its internal box, a rear wall  11 , and two opposite lateral walls  12 , only one being illustrated in  FIGS. 6 and 7 .  
      In the illustrated construction, each lateral wall  12  of the internal box of the cabinet  10  is provided with holes  12   a,  arranged according to the arrangement of the internal distribution of the refrigerator shelves and in which the rail portions or other supports for mounting the internal components of the cabinet are secured. The internal lateral hole assembly of the lateral walls of the cabinet  10  is object of a copending patent of the same applicant and will not be described in greater details herein.  
      According to the invention, the present shelf  20  comprises a generally flat frame, with a substantially rectangular contour and which is constructed in a plastic material or any other adequate simple or composite material.  
      The shelf  20  is constructed in such a way as to present, on each of its lateral edges  21 , two seating regions  22  longitudinally spaced from each other and which project slightly outwardly from the contour of the shelf  20 , to be slidingly mounted on supports provided on the lateral walls  12  of the internal box of the cabinet  10 , as described ahead.  
      The seating regions  22  can be positioned on a plane coinciding or not with the plane of the shelf  20 . In the illustrated construction, the seating regions  22  are defined by pins coplanar to each other, but which are incorporated externally to respective pending lateral flaps  24 , incorporated to the shelf  20  and which define portions of the lateral edges  21  of the latter. This construction makes the seating regions  22 , in the form of pins, to be disposed on a plane quite inferior to that of the upper face of the shelf  20 , as better illustrated in  FIGS. 2 and 4 .  
      For the shelf  20  to be displaceable inside the cabinet  10 , each seating region  22  is slidingly mounted on a respective rail portion  30  secured to a respective lateral wall  12  of the internal box of the cabinet  10  by any adequate means, or it can even be incorporated, in a single piece, to the structure of the internal box in a position predetermined in the project. However, the fixation of each rail portion  30  to the cabinet  10  is preferably made by fitting and retaining fixation means  31 , which can take the form of external orthogonal projections of the rail portions  30  to be fitted in respective holes  12   a  made in the lateral walls  12  of the internal box of the cabinet  10 .  
      In the illustrated construction, each rail portion  30  comprises a forwardly upwardly inclined lower rail extension  32 , with the lower end  32   a  being closed and defining the position in which the respective seating region  22  of the shelf  20  is maintained seated in the lower operative position of the shelf  20 , and an open upper end  32   b.  An upper rail extension  33  is further provided, disposed generally horizontally and having a rear end  33   a  disposed vertically aligned in relation to the lower end  32   a  of the lower rail extension  32 , and a front end  33   b  opened to the interior of the upper end  32   b  of the lower rail extension  32 .  
      The lower rail extension  32  and the upper rail extension  33  generally take the form of channels with a “U” shaped cross section, with the bottom wall seated against a respective lateral wall  12  of the internal box of the cabinet  10 , said channels having the width dimensioned to allow the guided sliding of the respective seating region  22  of the shelf  20 .  
      According to the illustrated construction, the two rail portions  30  positioned on each side of the shelf  20  are formed in a single piece, with the rear end  33   a  of the upper rail extension  33  of the rail portion  30 , which is more forwardly disposed, being incorporated to the front end  33   b  of the upper rail extension  33  of the rail portion  30  which is disposed behind the other rail portion by means of an intermediary rail extension  34 . The lower rail extension  32  and the upper rail extension  33  of each rail portion  30  are united to each other, in a single piece, by a closing wall  35  normally incorporated and which is coplanar to the free edge of the lateral walls of the channels that define said rail extensions.  
      With the construction described above, when the shelf  20  is in a lower operative position, the seating regions  22  thereof in the form of pins remain seated on the closed lower ends  32   a  of the respective lower rail extensions  32 , as illustrated in  FIGS. 1 and 2 . When the shelf  20  is forwardly pulled by the user, it has its seating regions  22  upwardly conducted, along the lower rail extensions  32 , until they reach the upper end  32   b  of the latter, when the shelf  20  occupies a transitional intermediary position, in which it is forwardly upwardly displaced in relation to the lower position and from which the shelf  20  can be horizontally backwardly displaced, with its seating regions  22  sliding along the upper rail extensions  33  until reaching an upper operative position, situated above and vertically spaced from the lower operative position, as illustrated in  FIGS. 3 and 4 . In the illustrated constructive example, the lower and upper operative positions are vertically aligned.  
      In the illustrated construction, the shelf  20  can occupy only the lower and upper operative positions, since the lower rail extensions  32  do not present intermediary regions configured to retain the respective seating regions  22  of the shelf  20 . It should be understood that this constructive variation is possible, provided that the inclined lower rail extensions  32  are medianly provided with at least one housing (not illustrated), in which the respective seating region  22  of the shelf  20  can be seated, for allowing the shelf  20  to be maintained in other operative positions in which it remains in the horizontal, or forwardly downwardly inclined, or forwardly upwardly inclined, depending on the positioning of the seating regions  22  along the respective lower rail extensions  32 .  
      In the illustrated embodiment, the upper rail extensions  33  are horizontal, making the transitional intermediary position to be substantially reached in the same level of the upper operative position. However, it is possible to construct the upper rail extensions  33  backwardly upwardly inclined, whereby the transitional intermediary position of the shelf  20  would be defined in an intermediary level between the lower and rear operative positions. The transitional intermediary position could be further associated with another lower operative position, provided that the joining region of the lower rail extension  32  and the upper rail extension  33  is configured for allowing the corresponding seating region  22  of the shelf  20  to be operatively seated thereon.  
      In order to improve the stability of the shelf  20  in the upper operative position, each upper rail extension  33  has its rear end  33   a  provided with a lower recess  33   c,  which is configured and dimensioned to define a concave cradle to receive a respective seating region  22  in the form of a pin of the shelf  20 .  
      Each pair of rail portions  30  in a single piece incorporates a front rail extension  36 , horizontally leveled and associated with the adjacent upper rail extension  33 , as if it were a continuation of the latter, and having an open front end for allowing the initial fitting for assembling the seating regions  22  of the shelf  20  on the rail portions  30 .  
      In order to prevent the shelf  20  from having its front seating regions  22  inadvertently pulled outwardly from the front rail portions  30  upon passing along the transitional intermediary position, the front rail extensions  36  are internally provided with a stop means  37  in the form of a latch, which is cut from the lower wall of the respective rail channel and which, by action of a small slide  38 , can occupy an inoperative position, liberating the passage of the seating regions  22  of the shelf  20  along the front rail extensions  36 , or an operative position, in which it prevents the seating regions  22  of the shelf  20  from passing along the front rail extensions  36 .  
      The upper operative position of the shelf  20  can be projected to reduce only the storage free gap located above said shelf, consequently increasing the storage free gap of the shelf disposed immediately below. However, the present arrangement can be designed and mounted in the cabinet  10  so that, in the upper operative position, the shelf  20  is retracted to a position defined close to the lower face of another shelf or dividing wall disposed immediately above the retractable shelf.  
      While only one embodiment of the invention has been illustrated, it should be understood that changes in the form and arrangement of the components could be made, without departing from the constructive concept defined in the appended claims.