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BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention pertains to the art of refrigerators and, more particularly, to an assembly, adapted to be arranged beneath a refrigerator cabinet, which includes structure for automatically closing or selectively maintaining open a supported refrigerator door, as well as structure for leveling of the overall refrigerator cabinet. 
     2. Discussion of the Prior Art 
     In the construction of refrigerators, it known in the art to provide biased door closure devices. Essentially, a spring or another mechanism is employed to give a small degree of resistance when force is used open a refrigerator. Such a system is necessary to prevent inadvertent opening of the refrigerator. Additionally, the biased door closure device also functions to close the door when left in the open position. In traditional systems, an arm is affixed at one end to the refrigerator door and at the other end to a spring, which is then connected to a part of the refrigerator cabinet. When the door is closed, the spring is compressed and in its relaxed position. When the door is opened, the arm is moved such that the spring is stretched, thus providing a closing force. 
     With a simple straight arm, there is a constant force biasing the door closed. While this is useful to ensure that the door closes automatically to both conserve energy and prevent spoilage of food contained within the refrigerator, it is impossible to maintain the door in an open position without holding the door open. Nevertheless, it is often beneficial to be able to leave the refrigerator door open without either holding or propping the door open. For example, when loading many items into or taking many items out of the refrigerator, it is largely inconvenient to have to open the door repeatedly. Moreover, cleaning the interior of the refrigerator becomes difficult because the door is constantly closing on the person cleaning the refrigerator. 
     Altering the configuration of the arm from a straight length creates an over-center reaction in the door. For example, U.S. Pat. No. 2,392,689 to Peglow discloses a curved arm used in an automatic door closure. This arm is curved such that, when the door is closed, the included spring assists in maintaining the door closed. When the door it initially opened, the spring gives a small amount of resistance sufficient to re-close the door when the opening force is removed. However, because the arm is curved, when the door is opened beyond a certain angle or degree, the specific shape of the curved arm actually biases the arm to a more open position. As a result, the spring is stretched as the door opens to this point, and is allowed to compress when the door is opened beyond this point. Accordingly, because the spring compresses as the door is opened to its widest position, the spring biases the door open. 
     Because refrigerators are often quite heavy, providing a wheel or other rolling assembly is particularly advantageous. Therefore, it has become a customary practice to equip such heavy domestic appliances with wheel assemblies to enhance mobility. When provided with a supporting wheel assembly, a heavy refrigerator can be readily moved by a single person to prepare for installation, repair, cleaning and other purposes. 
     Often times, it is also desirable to permit some degree of vertical adjustability between the refrigerator and the supporting surface. Specifically, it is desirable to enable leveling of a refrigerator. While the majority of household appliances are generally positioned on surfaces which are relatively level, it has still been found beneficiary to provide some vertical adjustability of the wheel assemblies to ensure precise leveling of the refrigerator. This is particularly advantageous when applied to a typical refrigerator such that the front portion of the refrigerator can be slightly elevated to ensure that the doors will open and close as desired, and not hinder the action of included door springs. 
     However, each of the systems described above is separate and distinct from one another such that multiple systems must be separately integrated into a refrigerator cabinet during manufacturing. As a result, time and expense are required during manufacturing in order to correctly install those systems. Therefore, there exists a need in the art for a quickly and easily installable assembly incorporating the advantages of both an over-center door closure and a vertically adjustable support. 
     SUMMARY OF THE INVENTION 
     An integrated refrigerator cabinet leveling and door closing assembly particularly adapted to be integrated into a single sub-assembly is described herein. More particularly, the invention includes a housing for both a door closure assembly and an adjustable refrigerator support which, when fully assembled, can be placed below and affixed to a refrigerator cabinet as a unitary component. 
     Specifically, the assembly includes a spring mounted to the housing to provide a biasing force to the refrigerator door. An arm connects the spring to the door such that moving the door from the closed position stresses the spring. A dampening element is employed to reduce noise generated upon stressing the spring in this manner. The arm is particularly configured to provide an over-center door closure to provide a closing force until the door is opened a certain degree. The arm also includes an elongated slot through which a mechanical fastener extends to limit the movement of the arm during pivoting of the door. The position of the mechanical fastener is selected to allow the arm to shift as the fastener slides along the slot, while permitting limited rotational movement of the arm. 
     The assembly also incorporates a support structure including a fixed pair of wheels provided to allow the refrigerator cabinet to roll. A vertically adjustable foot is provided to prevent movement when fully extended. A bevel gear drive arrangement is used to selectively retract and extend the foot. An adjusting shaft extends from the bevel gear to the front of the assembly housing to allow for adjustment in the height of each of the feet without easy access thereto. Simply rotating the adjusting shaft moves the respective foot either up or down, depending upon the direction of rotation of the adjusting shaft. The feet can actually be adjusted to raise the wheels off the supporting surface. In any event, an integrated door closing and refrigerator support/leveling assembly is defined that can be advantageously pre-assembled and attached to the remainder of the refrigerator as a single unit. 
     Additional objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment thereof when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an integrated refrigerator cabinet leveling and door closing assembly constructed in accordance the invention, with the assembly being attached to a refrigerator cabinet; 
         FIG. 2   a  is a perspective view of the integrated refrigerator cabinet leveling and door closing assembly, removed from the refrigerator cabinet with the door in the closed position; 
         FIG. 2   b  is a perspective view of the integrated refrigerator cabinet leveling and door closing assembly, removed from the refrigerator cabinet with the door in the extreme open position; 
         FIG. 3  is a side view of the integrated assembly, with the assembly attached to a refrigerator cabinet; and 
         FIG. 4  is a perspective view of the support structure used in the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With initial reference to  FIGS. 1 ,  2 A and  2 B, a refrigerator cabinet  6  is partially shown with a door  8 . Shown below cabinet  6  is a door closing and leveling assembly  10  constructed in accordance with the present invention. Assembly  10  includes a housing, generally indicated at  12 , including a frontal plate  15 , a rear plate  16 , and lateral side plates  20 , with a planar member  23  therebetween. A door closure structure  30 , which is part of a door closing and leveling assembly  10  as will be more fully described below, is shown protruding from a space between housing  12  and door  8 . Additionally, indicated at  35  is a leveling assembly, which will also be more fully described below. At this point it should be noted that  FIG. 1  only illustrates door closing and leveling assembly  10  used in a preferred manner. As shown, refrigerator cabinet  6  is a traditional, domestic side-by-side refrigerator/freezer and, as such, a second door closing and leveling assembly, having a mirror image to assembly  10 , would be used under the opposite side of cabinet  6 . 
       FIGS. 2A and 2B  show assembly  10  when door  8  is closed and open, respectively. Essentially, a tension spring  40 , which includes a coiled section  41  having arranged therein a dampening element  42  preferably constituted by a substantially cylindrical foam member, is attached at one end to lateral side plate  20  of housing  12 . The opposite end of spring  40  is attached to an arm  43 . Arm  43  generally includes a straight length section  46 , a first angled length section  49  and a second angled length section  51 . Straight length section  46  and first angled length section  49  form an obtuse angle, while first angled length section  49  and second angled length section  51  form an acute angle. Spring  40  is attached to arm  43  via any standard connection, but is shown with an elongated end  52  of spring  40  inserted through an aperture  53  in straight length section  46  of arm  43 . 
     Between the attachment with spring  40  and first angled length section  49 , arm  43  is provided with an elongated slot  54 . Slot  54  is of an oval shape and extends for a substantial length of straight length section  46 . Inserted through slot  54  is a mechanical fastener  58 . The opposite (hidden) end of fastener  58  is affixed to housing  12 . Fastener  58  may be of any conventional form, but is most preferably a threaded fastener, such as a screw or bolt, with a large surface area head. 
     The opposite end of arm  43  is second angled length section  51 . At the extreme end of angled length section  51 , a pin/bushing  63  is used to connected arm  43  to a plate  65 . Pin/bushing  63  essentially defines an axle (not separately labeled) extending completely through plate  65  and arm  43 . Pin/bushing  63  also includes a conventional bearing surface to permit a low friction rotation of plate  65  relative to arm  43 . A second pin/bushing  67  of substantially the same construction as pin/bushing  63  is used to connect a support bar  68  of cabinet  6  at a door pivot point on plate  65 . Plate  65  also includes a plurality of fastener holes  70   a ,  70   b  and  70   c  which permit connection to door  8 . Particularly, in the preferred embodiment, three fastener holes  70   a ,  70   b  and  70   c  are arranged in a triangular pattern to provide a secure link between plate  65  and door  8 . 
     The operation of door closure assembly  30  will be described with specific reference to  FIGS. 2A and 2B . Before door  8  is opened, spring  40  is in a relaxed state as shown in FIG.  2 A. Accordingly, any movement of door  8  is resisted by the internal forces of spring  40 . Fastener  58  is arranged in slot  54  at a position closest to first angled length section  49 . The dashed lines above housing  12  indicate the location of door  8  relative to housing  6  in closed and opened positions respectively. 
       FIG. 2B  shows the same structures as in  FIG. 2A , but with door  8  in an open position. First, because plate  65  is affixed to door  8  at fastener holes  70   a ,  70   b ,  70   c  and plate  65  is supported by cabinet  6  for pivotal movement via pin/bushing  67 , plate  65  rotates about pin/bushing  67  as door  8  is opened. As plate  65  rotates, arm  43  is pulled or extended because pin/bushing  63  connects arm  43  to plate  65 . Because fastener  58  is fixed in slot  54  with respect to arm  43 , movement of arm  43  causes relative movement between fastener  58  and slot  54 . The specific structure of fastener  58  in slot  54  permits extension and retraction of arm  43 , while allowing a degree of rotational movement about an axis defined by fastener  58 . This is clearly illustrated in comparing the position of arm  43  in  FIGS. 2A and 2B . More specifically, a comparison of the relative positions of arm  43  in  FIGS. 2A and 2B  reveals that arm  43  rotates as door  8  is opened. This rotational movement of arm  43  aids in establishing an over-center action necessary to provide a desired door-open biasing force. Specifically, due to the structure and movement of arm  43  as door  8  is opened, spring  40  is stretched until door  8  reaches a “critical point”. Due to the presence of dampening element  42  provided within coiled section  41 , unpleasant noises which could be generated during extension of spring  40  are minimized, and preferably eliminated. In accordance with the most preferred embodiment of the invention, dampening element  42  floats or slides within coiled section  41 , while being compressed when spring  40  is stretched. Dampening element  42  can be retained in coiled section  41  in various ways, including the use of one or more clips, tape, or the like (not shown). Before this critical point, removing the door opening force will cause door closure structure  30  to return door  8  to the closed position. However, once door  8  has crossed the critical point, removal of the door opening force will result in door closing structure  30  forcing door  8  into a more open position. 
       FIGS. 2A and 2B  additionally demonstrate the details of leveling assembly  35  in accordance with the invention. Adjacent to both frontal plate  15  and rear plate  16  are two support brackets  75   a ,  75   b  respectively. Each support bracket  75   a ,  75   b  serves as a foundation for a wheel  80  and a respective vertically adjustable foot  85   a ,  85   b . An adjusting shaft  90  extends from foot  85   b , through front plate  15 , and terminates in a driving end  92 . As will be more fully described below with reference to  FIG. 3 , driving end  92  is provided to allow for easy extension/retraction of rear foot  85   b , relative to housing  12 . A similar driving end  94  is associated with a shaft  95  and front foot  85   a.    
       FIG. 3  indicates the configuration of support structure  35  in greater detail. While only the support structure closest to frontal plate  15  is detailed, it is understood that the support structure closer to rear plate  16  is identical in construction and operation. Extending below planar member  23  of housing  12  is a portion of foot  85   a , which terminates in an enlarged, flat end  100 . Flat end  100  is essentially constituted by a flat circular member which extends at a right angle to a threaded shaft  105 . Shown protruding through frontal plate  15  is driving end  94  of adjusting shaft  95 . Connected to the opposite end of driving end  94  is a convention bevel gear  110 . The interrelation between bevel gear  110 , adjusting shaft  95  and foot  85   a  is such that applying a rotational force to driving end  94  of adjusting shaft  95  causes bevel gear  110  to mesh with a second bevel gear  112  attached to threaded shaft  105  to cause vertical movement of foot  85   a . As a result, flat end  100  is extended or retracted as driving end  94  is rotated. Because both adjusting shafts  90 ,  95  extend through frontal plate  15 , each foot  85   a ,  85   b  can be independently adjusted even without gaining access to the rear of cabinet  6 . 
       FIG. 4  indicates the preferred construction of support bracket  75   a . Of course, it is to be understood that support bracket  75   b  is correspondingly constructed. Essentially support bracket  75   a  includes a foot well  115  and a wheel well  117 , both in the general shape of an open rectangular prism, with a well separator  120  therebetween. Foot well  115  includes two upstanding sides  122   a ,  122   b , with a planar member  123  therebetween. A shaft aperture  125  is found in the center of planar member  123  for receiving threaded shaft  105  of respective foot  85   a . Wheel well  117  also includes two upstanding sides  127   a ,  127   b  with a planar member  128  therebetween. Upstanding sides  127   a  and  127   b  each has a respective axle aperture  130   a ,  130   b  for receiving and supporting a respective wheel  80 . Finally, bracket  75   a  includes a pair of wings  133   a ,  133   b  disposed on opposite sides of bracket  75 . Wings  133  are designed with holes  134  into which screws, bolts or other fasteners are placed to secure bracket  75  to housing  12 . 
     Leveling assembly  35  is designed to assist in moving and installing refrigerator cabinet  6 . Before moving cabinet  6 , adjusting shafts  90  and  95  are rotated to retract feet  85   a  and  85   b  off of the floor. Because wheels  80  extend below flat end  100  of feet  85   a ,  85   b  when feet  85   a ,  85   b  are fully retracted, wheels  80  support cabinet  6 . This allows cabinet  6  to roll on wheels  80 . Cabinet  6  may then be placed in a desired location. Once cabinet  6  has been properly positioned, adjusting shafts  90  and  95  are rotated to extend feet  85   a  and  85   b . That is, shafts  90  and  95  are rotated until each flat end  100  rests completely against the support surface below cabinet  6 . Once each of the flat ends  100  is supporting weight of cabinet  6 , the height of each foot  85   a ,  85   b  may be altered independently by rotating respective adjusting shafts  90 ,  95  to provide a final leveling of cabinet  6 . 
     As should be apparent from the above description, the cabinet leveling and door closing assembly  10  of the present invention provides an extremely compact arrangement that can be advantageously pre-assembled and then secured as an integrated unit to refrigerator cabinet  6  and door  8 . Assembly  10  combines structure used in supporting refrigerator  6  and door  8  for movement over a supporting surface, stabilizing refrigerator  6  in a desired, leveled condition, and controlling the opening and closing of door  6 . Although described with reference to a preferred embodiment, it should readily understood that various changes and/or modifications could be made to the invention without departing from the spirit thereof. For example, it should be understood that housing  12  may cover the entire lower surface of cabinet  6 , such that only one door closing and leveling assembly  11  is necessary. In addition, spring  40  need not be mounted to the specific location in housing  12  shown and described, as any location capable of providing the necessary support is sufficient. In any event, the invention is only intended to be limited by the scope of the following claims.

Summary:
An integrated door closing and leveling assembly for a refrigerator includes a spring biased door closure and an adjustable support integrated into a housing. The door closure includes an arm attached to the housing for relative sliding and pivoting movement, while being biased to a retracted position by a spring having an associated noise dampening element. The interaction between the spring and the arm is such that the spring provides a small degree of resistance to any opening force and also serves to maintain the door fully open once the door is opened beyond a critical point. The support structure houses both front and rear wheels for maneuvering the refrigerator, and feet for leveling and supporting purposes.