Patent Application
20060132008
Movable shelves in appliances and cabinets, such as in refrigerators are well known. Typically the shelves are formed from multiple components, including multiple materials in some instances. For example, U.S. Pat. No. 3,814,492 discloses a movable refrigerator shelf having side brackets 66 which are secured by welding to a support plate 68. The use of a welding bead as a fastener to hold together two separate parts requires extra assembly labor and materials, and hence increases the cost of the shelf. U.S. Pat. No. 6,488,347 discloses a one piece molded plastic frame for a refrigerator shelf that is molded around a separate glass shelf panel. U.S. Pat. No. 6,105,233 discloses a refrigerator shelf formed from a plurality of separate sheet metal stampings that are connected and held together by welds and receive a tempered glass shelf that has an elastic seal secured to its peripheral edge. Many other examples show similar shelf constructions.
A drawback of these existing shelf constructions is that extra labor and materials are required when the shelf is constructed of multiple components, whether those components are made from identical or different materials. Extra assembly and handling steps, and use of separate fasteners, including welding of separate parts, increase the cost of the shelves.
It would be an advance in the art if there were provided a single piece, metal shelf that could be formed without the need for assembly or use of fasteners for separate parts.
The present invention provides a single piece, metal shelf that may be formed without the need for assembly or use of fasteners to join or hold separate parts or components together.
In an embodiment, the invention comprises a shelf, usable in a refrigerator, which has a generally flat, horizontal support surface comprising a left edge, a right edge, a front edge and a rear edge. A first support arm extends along the left edge of the support surface and a second support arm extends along the right edge of the support surface. The first and second support arms are each connected by a substantially right angle bend to the support surface. The first and second support arms each extend rearwardly beyond the rear edge of the support surface. The support surface and the support arms are formed from a single piece of metal and are bent into a final configuration without the use of fasteners to join or hold separate parts or components together.
In an embodiment, the support surface includes a plurality of openings formed therein. For example, the plurality of openings may be a series of parallel slots extending generally front to rear. In one embodiment, the series of parallel slots may be two rows of parallel slots. In any configuration of openings, the openings may include downwardly depending walls which define the openings.
In an embodiment, the support arms each are provided with hooked tabs arranged to engage with a support ladder in the refrigerator.
In an embodiment, the support surface includes a raised rim extending around a perimeter of the surface.
In an embodiment, a downwardly extending lip may be formed at the front edge of the support surface.
In an embodiment, an upwardly extending ledge may be formed at the rear edge of the support surface.
The present invention is directed to a shelf which finds utility as a refrigerator shelf, although it could be used in other environments, including use in other appliances, such as freezers and also in various cabinets and shelving applications. In order to illustrate an embodiment of the invention, the shelf is illustrated as a shelf that can be used in a refrigerator, however, its use should not be limited to such an environment.
The shelves 28 are shown in greater detail in
In an embodiment, the support surface 34 includes a plurality of openings 52 formed therein. For example, as shown in
In any configuration of openings, as shown in greater detail in
In an embodiment, the support arms 44, 46 each are provided with hooked tabs 56 extending rearwardly of the rear edge 42 of the support surface 34 and are arranged to engage with the support ladders 30 in the refrigeration appliance 20. The tabs 56 engage in the slots of the ladders 30 and a rear edge 58 of the support arms 44, 46 abuts against the ladders to support the shelf 28 in a cantilevered fashion.
To provide additional strengthening for the shelf 28, in an embodiment, the support surface 34 includes a raised rim 60 extending around a perimeter 62 of the surface. The raised rim 60 is comprised of a short vertical wall segment 64 and a horizontal wall segment 66.
In an embodiment, a downwardly extending lip 68 may be formed at the front edge 40 of the support surface 34 or rim 60. This lip 68 extends across the entire front edge 40 and abuts the two support arms 44, 46. In some embodiments, the front lip 68 and support arms 44, 46 may be formed integrally, through appropriate bending and drawing operations, and in other embodiments, the front lip may be separate, but abutting the support arms.
In an embodiment, an upwardly positioned ledge 70 may be formed by a rear edge riser 72 at the rear edge 42 of the support surface 34 or rim 60. The ledge 70 may extend across the entire rear edge 42 of the support surface 34 and a portion of the support arms 44, 46 may depend directly from the ledge. Also, the upper hooked tab 56 may extend rearwardly from the support arms 44,46 at the level of the ledge 70.
To provide further strengthening for the shelf 28, one or more ribs or channels 74 may be provided in each support arm 44,46 extending generally in a front-to-rear direction.
The shelf 28, as described can be formed through a series of bends, draws and punches, and with the various strengthening bends and walls described allows the shelf to be formed from a thinner metal material than is presently used for refrigerator shelf construction. For example, presently used shelves have a thickness of about 0.060-0.070 inches, and the shelves made in accordance with the principles of the present invention may be formed of steel having a thickness of about 0.030 inches. In order to assure support strength for the attachment of the shelf 28 to the support ladder 30, the metal material forming the shelf may be folded over to provide a double thickness in the area of the tabs 56 (as best seen in
To form the shelf 28 of the present invention, a single flat sheet of metal, such as cold rolled commercial quality steel, drawn quality cold rolled steel or stainless steel (300 series), may be sequentially operated on in a progressive die press in which various of the openings 52 are formed, the outer perimeter shape is defined by cutting or punching, the various bends and draws are made and thus the shelf is completed from a single flat sheet to the finished configuration by mechanical shaping, all without further assembly or use of fasteners including welding of separate components or parts. Tack welding or clinching of the folded or bent portions of the single piece shelf can occur, for strengthening or securing purposes, during the operation of the progressive die press, without the gripping or positioning of additional components or parts.
The resulting unitary self 28 has the required structural strength while being very economical to manufacture. Following the formation of the shelf 28 in the press, the shelf may be coated with powder coating, high solids coating, or electro-coating paint systems and may be pointed a variety of colors and/or may carry a variety of decorative hot stamps or films.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art.
