Patent Publication Number: US-11047615-B1

Title: Flip up compartment floor

Description:
BACKGROUND 
     Refrigerators include various storage containers such as shelfs, drawers, and compartments that are arranged in the interior or on a door. Despite being able to adjust the location of some of the storage containers, large items sometimes still do not fit well in a desired location. 
     SUMMARY 
     In an example embodiment, a shelf is provided. The shelf includes, but is not limited to, a floor plate, a cam plate, and a first pin joint plate. The floor plate includes, but is not limited to, a front edge, a right edge, a left edge, and a back edge. The back edge is closest to a second wall when the floor plate is mounted adjacent the second wall. The right edge extends between the front edge and the back edge. The left edge extends between the front edge and the back edge. The cam plate is mounted to the floor plate to extend away from an upper surface of the floor plate. A top edge of the cam plate is opposite a bottom edge of the cam plate that is mounted to the upper surface of the floor plate. The top edge has a concave shape that curves inward toward the upper surface of the floor plate. The first pin joint plate is mounted to the floor plate to extend away from a lower surface of the floor plate. The first pin joint plate is configured to mate with a second pin joint plate mounted to a first wall when the floor plate is mounted to the first wall. The top edge of the cam plate is positioned to abut a tab mounted to the second wall when the floor plate is mounted adjacent the second wall and rotated toward the second wall. The upper surface of the floor plate faces the second wall when the floor plate is rotated toward the second wall. 
     In another example embodiment, a door is provided. The door includes, but is not limited to, an interior door plate, a right mounting ladder mounted to the interior door plate, a left mounting ladder mounted to the interior door plate, a shelf mounted to the right mounting ladder and to the left mounting ladder, and a rotatable shelf mounted to the right mounting ladder and to the left mounting ladder above the shelf. 
     In yet another example embodiment, a refrigerator is provided. The refrigerator includes, but is not limited to, a refrigeration system, a compartment, a right mounting ladder, a left mounting ladder, a shelf mounted to the right mounting ladder and to the left mounting ladder, and a rotatable shelf mounted to the right mounting ladder and to the left mounting ladder above the shelf. The compartment includes, but is not limited to, a plurality of walls and a door configured to provide access to an enclosed space defined by the plurality of walls and the door. The door is configured to provide access to an enclosed space defined by the plurality of walls and the door. The right mounting ladder and the left mounting ladder are mounted to the door. 
     Other principal features of the disclosed subject matter will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Illustrative embodiments of the disclosed subject matter will hereafter be described referring to the accompanying drawings, wherein like numerals denote like elements. 
         FIG. 1  depicts a left, front perspective view of an open refrigerator in accordance with an illustrative embodiment. 
         FIG. 2A  depicts a top, right, front perspective view of a shelf of the refrigerator of  FIG. 1  in accordance with an illustrative embodiment. 
         FIG. 2B  depicts a bottom, right, front perspective view of the shelf of  FIG. 2A  with a shelf door removed in accordance with an illustrative embodiment. 
         FIG. 2C  depicts a top, left, front perspective view of the shelf of  FIG. 2B  in accordance with an illustrative embodiment. 
         FIG. 2D  depicts a top, right, front perspective view of the shelf of  FIG. 2B  in accordance with an illustrative embodiment. 
         FIG. 2E  depicts a right, back perspective view of the shelf of  FIG. 2B  in accordance with an illustrative embodiment. 
         FIG. 3A  depicts a top, right, front perspective view of a rotatable shelf floor of the shelf of  FIG. 2A  in accordance with an illustrative embodiment. 
         FIG. 3B  depicts a top, left, front perspective view of the rotatable shelf floor of  FIG. 3A  in accordance with an illustrative embodiment. 
         FIG. 3C  depicts a bottom, left, front perspective view of the rotatable shelf floor of  FIG. 3A  in accordance with an illustrative embodiment. 
         FIG. 3D  depicts a bottom, left, back perspective view of the rotatable shelf floor of  FIG. 3A  in accordance with an illustrative embodiment. 
         FIG. 3E  depicts a bottom, right, back perspective view of the rotatable shelf floor of  FIG. 3A  in accordance with an illustrative embodiment. 
         FIG. 3F  depicts a front view of the rotatable shelf floor of  FIG. 3A  in accordance with an illustrative embodiment. 
         FIG. 3G  depicts a right side view of the rotatable shelf floor of  FIG. 3A  in accordance with an illustrative embodiment. 
         FIG. 4A  depicts a top, right, front perspective view of the shelf of  FIG. 2A  with the shelf door and the rotatable shelf floor removed in accordance with an illustrative embodiment. 
         FIG. 4B  depicts a zoomed bottom, right, front perspective view of the shelf of  FIG. 4A  in accordance with an illustrative embodiment. 
         FIG. 4C  depicts a zoomed top, front perspective view of the shelf of  FIG. 4A  in accordance with an illustrative embodiment. 
         FIG. 4D  depicts a zoomed bottom, right, back perspective view of the shelf of  FIG. 4A  in accordance with an illustrative embodiment. 
         FIG. 5A  depicts a right side view of the shelf of  FIG. 2A  with a shelf right side wall removed and a rotatable shelf in a down position in accordance with an illustrative embodiment. 
         FIG. 5B  depicts a right side view of the shelf of  FIG. 5A  with the rotatable shelf in a partially up position in accordance with an illustrative embodiment. 
         FIG. 5C  depicts a right side view of the shelf of  FIG. 5A  with the rotatable shelf in a fully up position in accordance with an illustrative embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a left, front, perspective view of a refrigerator  100  is shown in accordance with an illustrative embodiment. Refrigerator  100  may include a plurality of compartments or cooling zones. Refrigerator  100  may include a freezer compartment door  102 , a refrigerator compartment door  103 , a right side wall  104 , a back wall  106 , a left side wall  108 , a top wall  110 , a bottom wall  112 , and a divider wall  114 . In the illustrative embodiment, freezer compartment door  102  is rotatably mounted to top wall  110  and bottom wall  112  adjacent left side wall  108  using two hinges, and refrigerator compartment door  103  is rotatably mounted to top wall  110  and bottom wall  112  adjacent right side wall  104  using another two hinges. In alternative embodiments, freezer compartment door  102  and/or refrigerator compartment door  103  may be rotatably mounted to different walls of refrigerator  100  using a fewer or a greater number of hinges. 
     Freezer compartment door  102  provides access to a freezer compartment defined by top wall  110 , left side wall  108 , bottom wall  112 , back wall  106 , divider wall  114 , and freezer compartment door  102  when freezer compartment door  102  is in a closed position. Refrigerator compartment door  103  provides access to a refrigerated compartment defined by top wall  110 , right side wall  104 , bottom wall  112 , back wall  106 , divider wall  114 , and refrigerator compartment door  103  when refrigerator compartment door  103  is in a closed position. 
     Divider wall  114  separates the freezer compartment from the refrigerator compartment. In the illustrative embodiment, divider wall  114  extends vertically between top wall  110  and bottom wall  112 . Of course, in alternative embodiments, divider wall  114  may extend horizontally to separate the two compartments with the freezer compartment either above or below the refrigerated compartment. Additionally, in alternative embodiments, the locations of the freezer compartment and the refrigerated compartment may be reversed. Further, refrigerator  100  may include a greater or a fewer number of compartments in various arrangements horizontally or vertically with respect to each other. 
     Though shown in the illustrative embodiment as forming a generally rectangular shaped enclosure, refrigerator  100  may form any shaped enclosure including other polygons as well as circular or elliptical enclosures. As a result, freezer compartment door  102 , refrigerator compartment door  103 , and the walls forming refrigerator  100  may have any shape including other polygons as well as circular or elliptical shapes. 
     Various storage devices may be housed within the enclosed space(s) of refrigerator  100 . For example, zero or more drawers  120 , shelves  122 , or other receptacles may be mounted within the freezer compartment and the refrigerator compartment. An ice maker/dispenser  124  may be mounted within the freezer space to make and store ice. Zero or more door shelves  116  may be mounted to either or both of freezer compartment door  102  and refrigerator compartment door  103 . 
     The storage devices may mount to various walls of refrigerator  100 , to freezer compartment door  102 , and/or to refrigerator compartment door  103  using one or more ladders  126  that are mounted to a wall of refrigerator  100 , a wall of freezer compartment door  102 , or a wall of refrigerator compartment door  103 . For example, a right mounting ladder and a left mounting ladder of the one or more ladders  126  may be mounted to an interior door plate  128  of refrigerator compartment door  103 . The one or more ladders  126  may be configured so that a mounting mechanism of a respective drawer, shelf, or other receptacle is attached to a rung of the ladder or between a pair of ladder rungs as understood by a person of skill in the art. For example, the mounting mechanism may include a hook that is mounted to the storage device and over a rung of the ladder or between a pair of ladder rungs to position the storage device within the enclosed space, on freezer compartment door  102 , or on refrigerator compartment door  103 . As another example, the mounting mechanism may include a pin that is mounted to the storage device and inserted in a rung of the ladder or between a pair of ladder rungs to position the storage device within the enclosed space, on freezer compartment door  102 , or on refrigerator compartment door  103 . As yet another example, the mounting mechanism may include an aperture that is mounted to the storage device and to a pin mounted as a rung of the ladder to position the storage device within the enclosed space, on freezer compartment door  102 , or on refrigerator compartment door  103 . Other mounting mechanisms may be used such as adhesive, soldering, etc. Zero or more of the storage devices may be mountable to different ladder rungs to change a position of the storage container within the enclosed space, on freezer compartment door  102 , or on refrigerator compartment door  103 . 
     A first shelf  118  is an illustrative shelf that can be mounted to either or both of freezer compartment door  102  and refrigerator compartment door  103 . First shelf  118  further may be mounted to one of the plurality of walls of refrigerator  100  in alternative embodiments. For example, first shelf  118  may be mounted to right side wall  104 , back wall  106 , left side wall  108 , or divider wall  114 . 
     As understood by a person of skill in the art, the walls that form refrigerator  100  include insulation to assist in maintenance of the desired temperature in the freezer and refrigerator compartments. Electrical wiring and various conduits may further be located in the walls. 
     A temperature of one or more refrigerated compartments of refrigerator  100  is maintained at an adequate temperature to preserve fresh food using a refrigeration system (not shown) as understood by a person of skill in the art, and a temperature of one or more freezer compartments is maintained at an adequate temperature to maintain food stored therein in a frozen state using a second refrigeration system (not shown) as understood by a person of skill in the art. 
     A refrigerator controller (not shown) may control a flow of refrigerant through each refrigeration system of refrigerator  100 . Refrigerator  100  may include one or more refrigeration systems. Refrigeration system components such as a compressor, a condenser, an evaporator, a dryer, etc. may be mounted to various walls of refrigerator  100  either within the walls, on an exterior of the walls relative to refrigerator  100 , and/or on an interior of the walls relative to refrigerator  100 . 
     Use of directional terms, such as top, bottom, right, left, front, back, etc. are merely intended to facilitate reference to the various surfaces and elements of the described structures relative to the orientations shown in the drawings and are not intended to be limiting in any manner. For consistency, the components of refrigerator  100  are labeled such that freezer compartment door  102  and refrigerator compartment door  103  define a front of refrigerator  100 . However, the components of first shelf  118  are labeled assuming refrigerator compartment door  103  is open as shown in  FIG. 1  and a user is positioned looking at first shelf  118 . 
     Referring to  FIG. 2A , first shelf  118  is shown in accordance with an illustrative embodiment. First shelf  118  may include a shelf door  200 , a shelf left side wall  202 , a shelf back wall  204 , a shelf right side wall  206 , a shelf top wall  208 , a shelf bottom wall  210 , and a rotatable shelf bottom wall  212 . A door handle  214  may be formed in shelf door  200  to facilitate opening and closing of shelf door  200 . In the illustrative embodiment, shelf door  200  is mounted for rotation in a clockwise direction relative to a top, front edge where shelf door  200  mounts adjacent shelf top wall  208  and between shelf left side wall  202  and shelf right side wall  206 . In alternative embodiments, first shelf  118  may not include shelf door  200 , may include a partial front wall to maintain items placed on first shelf  118  on first shelf  118 , or may not include a front wall at all. 
     First shelf  118  further may include zero or more divider walls  216  that extend from shelf back wall  204  toward shelf door  200 . The one or more divider walls  216  define separate storage areas along shelf bottom wall  210  and rotatable shelf bottom wall  212 . 
     First shelf  118  further may include a right mounting mechanism  218  and a left mounting mechanism  220 . In the illustrative embodiment, right mounting mechanism  218  and left mounting mechanism  220  are hooks that protrude outward away from shelf right side wall  206  and shelf left side wall  202 , respectively, or from shelf back wall  204 . Right mounting mechanism  218  and left mounting mechanism  220  are configured to mount to a right ladder (not shown) and a left ladder (not shown), respectively, to position first shelf  118  within the enclosed space, on freezer compartment door  102 , or on refrigerator compartment door  103 . In the illustrative embodiment, first shelf  118  is mounted to a top of interior door plate  128  of refrigerator compartment door  103 . Again, other mounting mechanisms may be used in alternative embodiments to mount first shelf  118  at various locations within the enclosed space, on freezer compartment door  102 , or on refrigerator compartment door  103 . In alternative embodiments, first shelf  118  may be mounted within other types of enclosed spaces or to other doors and not necessarily those of a refrigerator such as refrigerator  100 . Application within refrigerator  100  is merely for illustration. 
     Referring to  FIG. 2B , a bottom, right, front perspective view of first shelf  118  with shelf door  200  removed is shown in accordance with an illustrative embodiment. Referring to  FIG. 2C , a top, left, front perspective view of first shelf  118  with shelf door  200  removed is shown in accordance with an illustrative embodiment. Referring to  FIG. 2D , a top, right, front perspective view of first shelf  118  with shelf door  200  removed is shown in accordance with an illustrative embodiment. Referring to  FIG. 2E , a right, back perspective view of first shelf  118  with shelf door  200  removed is shown in accordance with an illustrative embodiment. The one or more components of first shelf  118  may be formed of one or more materials, such as metal, glass, and/or plastic having a sufficient strength and rigidity to support food items or other items, for example, stored in refrigerator  100  or other device to which first shelf  118  is mounted. 
     In the illustrative embodiment, rotatable shelf bottom wall  212  is mounted to be rotatable from a horizontal position as shown in  FIGS. 2A-2E  to an approximately vertical position as shown in  FIG. 5C . In the illustrative embodiment, first shelf  118  includes shelf bottom wall  210  that is not rotatable. In alternative embodiments, first shelf  118  may not include shelf bottom wall  210  that is not rotatable such that an entirety of a bottom wall of first shelf  118  is rotatable from the horizontal position to the approximately vertical position. 
     Referring to  FIG. 3A , a top, right, front perspective view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. Referring to  FIG. 3B , a top, left, front perspective view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. Referring to  FIG. 3C , a bottom, left, front perspective view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. Referring to  FIG. 3D , a bottom, left, back perspective view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. Referring to  FIG. 3E , a bottom, right, back perspective view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. Referring to  FIG. 3F , a front view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. Referring to  FIG. 3G , a right side view of rotatable shelf bottom wall  212  is shown in accordance with an illustrative embodiment. 
     Rotatable shelf bottom wall  212  may include a floor plate  300 , a handle  310 , a left cam plate  314 , a right cam plate  322 , a first, left pin joint plate  316 , and a first, right pin joint plate  324 . Floor plate  300  may include a front edge  302 , a left edge  304 , a back edge  306 , and a right edge  308 . Back edge  306  is closest to shelf back wall  204  or, for example, to interior door plate  128  when rotatable shelf bottom wall  212  is mounted adjacent interior door plate  128  and first shelf  118  does not include shelf back wall  204 . Right edge  308  extends between front edge  302  and back edge  306 . Left edge  304  extends between front edge  302  and back edge  306 . 
     Floor plate  300  may be generally flat so that an item can be placed on a top surface of floor plate  300  for storage of the item. In the illustrative embodiment, front edge  302 , left edge  304 , and right edge  308  are generally flat while back edge  306  slopes downwards. Though shown in the illustrative embodiment as forming a generally rectangular shaped plate, rotatable shelf bottom wall  212  may form other shapes including other polygons as well as circular or elliptical plates. 
     In the illustrative embodiment, handle  310  is mounted to a lower surface of floor plate  300  to extend away from the lower surface at an angle, and handle  310  is positioned closer to front edge  302  than back edge  306 . A finger hold  312  may extend from handle  310  and provide a surface that a user can press against to pull rotatable shelf bottom wall  212  back to or toward the horizontal position though the user can touch other portions of handle  310  as well to pull rotatable shelf bottom wall  212  back to or toward the horizontal position. In an alternative embodiment, handle  310  may extend from front edge  302  or other surfaces of floor plate  300 . 
     Left cam plate  314  is mounted to floor plate  300  to extend away from an upper surface of floor plate  300 . A top edge of left cam plate  314  is opposite a bottom edge of left cam plate  314  that is mounted to the upper surface of floor plate  300 . The top edge of left cam plate  314  has a concave shape that curves inward toward the upper surface of floor plate  300 . In the illustrative embodiment, left cam plate  314  is mounted to floor plate  300  adjacent back edge  306 , is at least partially above first, left pin joint plate  316  when floor plate  300  is in a horizontal position, and is centered above first, left pin joint plate  316  in a direction from front edge  302  to back edge  306 . The top edge of left cam plate  314  is elongated to extend from back edge  306  toward front edge  302 . 
     A left notch  320  is formed in the top edge of left cam plate  314 . An end of a left tab  416  (shown referring to  FIGS. 4B-4D ) engages with left notch  320  when floor plate  300  is rotated to extend in a direction that is approximately parallel to shelf back wall  204  or, for example, to interior door plate  128  when rotatable shelf bottom wall  212  is mounted adjacent interior door plate  128  and first shelf  118  does not include shelf back wall  204 . Left notch  320  is formed in a front half of the top edge of left cam plate  314 . As measured relative to a center of the elongated top edge, the front half of the top edge is on a side of the center toward front edge  302 . 
     First, left pin joint plate  316  is mounted to floor plate  300  to extend away from a lower surface of floor plate  300 . A bottom edge of first, left pin joint plate  316  is opposite a top edge of first, left pin joint plate  316  that is mounted to the lower surface of floor plate  300 . The bottom edge of first, left pin joint plate  316  has a concave shape that curves inward toward the lower surface of floor plate  300  though other shapes may be used in alternative embodiments. In the illustrative embodiment, first, left pin joint plate  316  is mounted to floor plate  300  adjacent back edge  306 . The bottom edge of first, left pin joint plate  316  extends from back edge  306  toward front edge  302 . 
     First, left pin joint plate  316  is configured to mate with a second, left pin joint plate  400  (shown referring to  FIGS. 4A, 4B, and 4D ) mounted to shelf bottom wall  210 . In an alternative embodiment, first, left pin joint plate  316  may be mounted to extend from other walls of refrigerator  100  (or other device to which first shelf  118  is mounted) or of first shelf  118 , such as shelf left side wall  202 . For example, first, left pin joint plate  316  includes a left pin  318  that extends outward in a generally perpendicular direction toward second, left pin joint plate  400 , and second, left pin joint plate  400  includes a left aperture  402  formed horizontally through second, left pin joint plate  400 . Left pin  318  is sized and shaped to fit within left aperture  402 . Rotatable shelf bottom wall  212  is mounted to first shelf  118  by inserting left pin  318  into left aperture  402 . A length that left pin  318  extends perpendicular from first, left pin joint plate  316  may be selected to provide sufficient strength and rigidity to support items on floor plate  300  while being flexible enough for insertion into left aperture  402 . In an alternative embodiment, left aperture  402  may be formed through first, left pin joint plate  316 , and left pin  318  may extend from second, left pin joint plate  400  toward first, left pin joint plate  316 . Other mechanisms for mounting rotatable shelf bottom wall  212  for rotation upward relative to other components of first shelf  118  may be used in alternative embodiments. 
     Right cam plate  322  is mounted to floor plate  300  to extend away from an upper surface of floor plate  300 . A top edge of right cam plate  322  is opposite a bottom edge of right cam plate  322  that is mounted to the upper surface of floor plate  300 . The top edge of right cam plate  322  has a concave shape that curves inward toward the upper surface of floor plate  300 . In the illustrative embodiment, right cam plate  322  is mounted to floor plate  300  adjacent back edge  306 , is at least partially above first, right pin joint plate  324  when floor plate  300  is in a horizontal position, and is centered above first, right pin joint plate  324  in a direction from front edge  302  to back edge  306 . The top edge of right cam plate  322  is elongated to extend from back edge  306  toward front edge  302 . 
     A right notch  328  is formed in the top edge of right cam plate  322 . An end of a right tab  420  (shown referring to  FIGS. 4C and 4D ) engages with right notch  328  (as shown referring to  FIG. 5C ) when floor plate  300  is rotated to extend in a direction that is approximately parallel to shelf back wall  204  or, for example, to interior door plate  128  when rotatable shelf bottom wall  212  is mounted adjacent interior door plate  128  and first shelf  118  does not include shelf back wall  204 . Right notch  328  is formed in a front half of the top edge of right cam plate  322 . As measured relative to a center of the elongated top edge, the front half of the top edge is on a side of the center toward front edge  302 . 
     First, right pin joint plate  324  is mounted to floor plate  300  to extend away from the lower surface of floor plate  300 . A bottom edge of first, right pin joint plate  324  is opposite a top edge of right pin joint plate  324  that is mounted to the lower surface of floor plate  300 . The bottom edge of first, right pin joint plate  324  has a concave shape that curves inward toward the lower surface of floor plate  300  though other shapes may be used in alternative embodiments. In the illustrative embodiment, first, right pin joint plate  324  is mounted to floor plate  300  adjacent back edge  306 . The bottom edge of first, right pin joint plate  324  extends from back edge  306  toward front edge  302 . 
     First, right pin joint plate  324  is configured to mate with a second, right pin joint plate  406  (shown referring to  FIGS. 4B and 4D ) mounted to shelf bottom wall  210 . In an alternative embodiment, first, right pin joint plate  324  may be mounted to extend from other walls of refrigerator  100  (or other device to which first shelf  118  is mounted) or of first shelf  118 , such as shelf right side wall  206 . For example, first, right pin joint plate  324  includes a right pin  326  that extends outward in a generally perpendicular direction toward second, right pin joint plate  406 , and second, right pin joint plate  406  includes a right aperture  408  formed horizontally through second, right pin joint plate  406 . Right pin  326  is sized and shaped to fit within right aperture  408 . Rotatable shelf bottom wall  212  is mounted to first shelf  118  by inserting right pin  326  into right aperture  408 . A length that right pin  326  extends perpendicular from first, right pin joint plate  324  may be selected to provide sufficient strength and rigidity to support items on floor plate  300  while being flexible enough for insertion into right aperture  408 . In an alternative embodiment, right aperture  408  may be formed through first, right pin joint plate  324 , and right pin  326  may extend from second, right pin joint plate  406  toward first, right pin joint plate  324 . 
     Right cam plate  322  is mounted to floor plate  300  adjacent a right corner defined where right edge  308  meets back edge  306 , and left cam plate  314  is mounted to floor plate  300  adjacent a left corner defined where left edge  304  meets back edge  306 . Rotatable shelf bottom wall  212  may include a fewer or a greater number of cam plates at various locations along back edge  306 . In an illustrative embodiment, rotatable shelf bottom wall  212  may be formed using a molding process so that some or all of the described elements may be integrally formed together. 
     To provide a flat mating surface with shelf bottom wall  210 , floor plate  300  may include a left floor notch  330  formed in left edge  304  that defines a left recessed wall  332  and a right floor notch  334  formed in right edge  308  that defines a right recessed wall  336 . Left floor notch  330  forms an overhang sized and shaped to abut a left support shelf  404  (shown referring to  FIGS. 4A-4D ) that extends from shelf bottom wall  210  toward shelf right side wall  206  when rotatable shelf bottom wall  212  is in the horizontal position. Right floor notch  334  forms an overhang sized and shaped to abut a right support shelf  410  (shown referring to  FIGS. 4B and 4C ) that extends from a bottom edge of shelf right side wall  206  toward shelf left side wall  202  when rotatable shelf bottom wall  212  is in the horizontal position. Left support shelf  404  and right support shelf  410  are configured to have a sufficient size and rigidity to support floor plate  300  when items are placed on floor plate  300 . Depending on a location of rotatable shelf bottom wall  212  within first shelf  118 , left support shelf  404  and/or right support shelf  410  may extend from shelf bottom wall  210 , shelf right side wall  206 , shelf left side wall  202 , and/or shelf back wall  204 . 
     Referring to  FIG. 4A , a top, right, front perspective view of first shelf  118  with shelf door  200  and rotatable shelf bottom wall  212  removed is shown in accordance with an illustrative embodiment. Referring to  FIG. 4B , a zoomed bottom, right, front perspective view of first shelf  118  with shelf door  200  and rotatable shelf bottom wall  212  removed is shown in accordance with an illustrative embodiment. Referring to  FIG. 4C , a zoomed top, front perspective view of first shelf  118  with shelf door  200  and rotatable shelf bottom wall  212  removed is shown in accordance with an illustrative embodiment. Referring to  FIG. 4D , a zoomed bottom, right, back perspective view of first shelf  118  with shelf door  200  and rotatable shelf bottom wall  212  removed is shown in accordance with an illustrative embodiment. 
     Left tab  416  is formed by a pair of apertures  414  formed through shelf back wall  204  along a lower edge  412  of shelf back wall  204 . Right tab  420  is formed by a pair of apertures  418  formed through shelf back wall  204  along lower edge  412  of shelf back wall  204 . Left tab  416  is positioned so that left cam plate  314  abuts left tab  416  to provide a spring force against the top edge of left cam plate  314  when rotatable shelf bottom wall  212  is rotated upwards from the horizontal position. Right tab  420  is positioned so that right cam plate  322  abuts right tab  420  to provide a spring force against the top edge of right cam plate  322  when rotatable shelf bottom wall  212  is rotated upwards from the horizontal position. Lower edge  412  of shelf back wall  204  is curved towards shelf door  200  in an illustrative embodiment. 
     Referring to  FIG. 5A , a right side view of first shelf  118  with shelf right side wall  206  removed and with rotatable shelf bottom wall  212  in the horizontal position is shown in accordance with an illustrative embodiment. A lower edge of left tab  416  and a lower edge of right tab  420  abut back edge  306  of floor plate  300 . 
     Referring to  FIG. 5B , a right side view of first shelf  118  with shelf right side wall  206  removed and with rotatable shelf bottom wall  212  in a partially up position is shown in accordance with an illustrative embodiment. The spring force provided by left tab  416  against the top edge of left cam plate  314  and by right tab  420  against the top edge of right cam plate  322  may be selected to hold rotatable shelf bottom wall  212  at the rotated position against the force of gravity. 
     Referring to  FIG. 5C , a right side view of first shelf  118  with shelf right side wall  206  removed and with rotatable shelf bottom wall  212  in a fully up position is shown in accordance with an illustrative embodiment. In the illustrative embodiment, the fully up position is approximately vertical or parallel to shelf back wall  204 . When rotated to the fully up position, left tab  416  abuts left notch  320  of the top edge of left cam plate  314  and right tab  420  abuts right notch  328  of the top edge of right cam plate  322  to stop further rotation of rotatable shelf bottom wall  212  and to hold rotatable shelf bottom wall  212  in the fully up position. 
     Referring again to  FIG. 1 , first shelf  118  is mounted above another storage device such as a lower door shelf. Rotatable shelf bottom wall  212  allows items that are taller than a distance between the floor of the lower door shelf and rotatable shelf bottom wall  212  to be placed in the lower door shelf by rotating rotatable shelf bottom wall  212  upward. In the illustrative embodiment, shelf door  200 , shelf left side wall  202 , shelf back wall  204 , shelf right side wall  206 , and shelf top wall  208  surround shelf bottom wall  210  and rotatable shelf bottom wall  212  to form an enclosed shelf though this is not required in alternative embodiments though inclusion of shelf door  200  protects against items falling from shelf bottom wall  210  and rotatable shelf bottom wall  212  and from the lower door shelf when rotatable shelf bottom wall  212  is rotated upwards. 
     As used in this disclosure, the term “mount” is intended to define a structural connection between two or more elements and includes join, unite, connect, couple, associate, insert, hang, hold, affix, attach, fasten, bind, paste, secure, bolt, screw, rivet, solder, weld, glue, adhere, form over, layer, and other similar terms. The phrases “mounted on” and “mounted to” include any interior or exterior portion of the elements referenced. These phrases also encompass direct mounting (in which the referenced elements are in direct contact) and indirect mounting (in which the referenced elements are not in direct contact). Elements referenced as mounted to each other herein may further be integrally formed together, for example, using a molding process as understood by a person of skill in the art. As a result, elements described herein as being mounted to each other need not be discrete structural elements. 
     The word “illustrative” is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “illustrative” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Further, for the purposes of this disclosure and unless otherwise specified, “a” or “an” means “one or more”. Still further, using “and” or “or” in the detailed description is intended to include “and/or” unless specifically indicated otherwise. The illustrative embodiments may be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques to produce software, firmware, hardware, or any combination thereof to control a computer to implement the disclosed embodiments. 
     The foregoing description of illustrative embodiments of the disclosed subject matter has been presented for purposes of illustration and of description. It is not intended to be exhaustive or to limit the disclosed subject matter to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed subject matter. The embodiments were chosen and described in order to explain the principles of the disclosed subject matter and as practical applications of the disclosed subject matter to enable one skilled in the art to utilize the disclosed subject matter in various embodiments and with various modifications as suited to the particular use contemplated.