Patent Description:
Such a shelf is shown in <CIT>. The expanded mesh panel is obtained by cutting a large number of parallel slits in a sheet metal piece and subsequently expanding the piece perpendicularly to the slits. The expanded piece may then be given a surface treatment such as powder coating to provide a desired color, and cover burrs etc. formed in the expanding process. One advantage with having an expanded metal mesh panel on a shelf top surface is that the surface becomes relatively skid free as compared to a smooth sheet metal surface. Further, the surface becomes ventilated to some extent.

One problem with shelfs of the above-mentioned type is how to make them more versatile.

<CIT> describes a refrigerator with shelves composed of porous plates thermally connected to cooling tubes. The porous plates may be mesh-formed.

One object of the present disclosure is therefore to provide a more versatile shelf. This object is achieved by a shelf as defined in claim <NUM>. More specifically, in a shelf of the initially mentioned kind, the shelf comprises at least one unexpanded area in between two expanded areas, along the width of the shelf. This means that an area in between the sheet metal edges, at which the piece is stretched, is smooth and lends itself well to applying different reinforcement measures. For instance, the unexpanded area can be spot welded to a reinforcement bracket or beam. Thanks to such measures, the shelf becomes stronger and better suited to carry heavy loads. Therefore, the shelf becomes more versatile.

An unexpanded area may be arranged centred along the shelf, dividing the shelf in two, for instance equal areas of expanded metal mesh, and the shelf further comprises a reinforcement, which is arranged at a bottom side of the shelf. By allowing attachment of a reinforcement at or close to the mid-point of the depth of the shelf, the shelf becomes stronger and capable of carrying a greater load.

The reinforcement may be provided as a beam bent to form a U-shape in cross-section. This achieves an increased second area of moment at the unexpanded location.

The reinforcement has flanges adapted to be connected to the unexpanded area at the lower surface thereof, which facilitates using spot-welding or other fastening arrangements for attaching the reinforcement at the unexpanded area.

The reinforcement at the bottom surface of the shelf may extend along the length of the unexpanded area, preferably at least along most of the length thereof.

The shelf may further comprise unexpanded areas along the front and rear edges of the shelf. Such unexpanded areas may be bent out of the plane of the top surface to provide a stronger shelf.

Side pieces may be fitted to the edges perpendicular to the unexpanded areas.

The present disclosure relates to a mesh shelf being formed partly by expanded sheet metal. A main piece of such a shelf is shown in <FIG>.

A piece of sheet metal is provided with a great number of small, parallel slits, running in successive parallel rows, by punching. The locations of the slits are offset between adjacent rows, usually such that the mid-point of a slit in one row is located at the interval in between two adjacent slits in the other. Every second row may therefore be in-phase with each other. Once the slits are punched in a desired pattern, the sheet metal piece is drawn in a direction perpendicular to the slits, expanding the piece and forming a rhombus-shaped small opening at the location of each slit.

In the shown embodiment of <FIG>, a rectangular piece of sheet metal is used, which may have a thickness in the range <NUM>-<NUM>, typically <NUM>, and may comprise steel or possibly e.g. aluminum. According to the invention, the sheet metal is provided with slits in the above manner in two wide bands along the piece and is expanded to correspondingly form two expanded portions <NUM>, <NUM>. In between those portions <NUM>, <NUM>, an unexpanded portion <NUM> is maintained therebetween. This is done simply by not punching slits in that portion. Likewise, the edge portions <NUM>, <NUM> are left unexpanded.

Thanks to the unexpanded portion <NUM>, which in the illustrated case is located in the middle of the shelf <NUM>, a reinforcement <NUM> may be provided under the unexpanded portion <NUM>, as will be illustrated in more detail. The unexpanded portion <NUM> provides a smooth and flat sheet metal surface to which a reinforcement may for instance be spot welded, a process which would be significantly more difficult had the shelf <NUM> been expanded at that location. Other ways of attaching reinforcements such as soldering or gluing could be considered and also benefits from being able to attach to a smooth surface. The unexpanded portion <NUM> may in the same way be connected to a side piece <NUM> (cf. <FIG>), which will be described in more detail. Therefore, the unexpanded portion <NUM> allows making a mesh board stronger, making it capable of carrying a greater load.

Providing more expanded and unexpanded areas on a board is possible as will be described.

Although the shelf <NUM> may in principle be square, usually, the shelf will have a main direction of extension <NUM> where it has its longest extension, as indicated in <FIG>. The shelf main piece is usually expanded in the direction of the depth <NUM> of the shelf. Locating an unexpanded portion <NUM> at the mid-point of the shelf depth <NUM> may be preferred to provide an increased stiffness when the shelf is intended to be suspended between its short ends.

<FIG> shows a side view of the mesh shelf of <FIG> shows an enlarged part thereof. As shown in <FIG>, once the expansion has been carried out to accomplish the mesh structure, a reinforcement beam <NUM> is attached on the lower face of the unexpanded portion <NUM>. This may be done for instance by spot welding. Further, the edges <NUM>, <NUM>, that are parallel with the expanded mesh stripes <NUM>, <NUM> and which may be unexpanded as well, may be bent to provide U-shaped cross sections <NUM>, <NUM>. This makes the shelf more stable by providing a significant second moment of area as compared to a flat structure, and together with the reinforcement beam <NUM> in between those edges makes the shelf capable of carrying a substantial load even if being made up by a relatively thin sheet material. The U-shape will not expose any, potentially sharp, sheet metal edges as the outer long edges of the shelf. Needless to say, the edges <NUM>, <NUM> may be bent in other ways.

<FIG> illustrates the attachment of the reinforcement beam <NUM> on the lower surface of the unexpanded portion <NUM>. As shown, the reinforcement beam <NUM> according to the invention comprises flanges <NUM> at its side edges which may be parallel with each other. Those flanges <NUM> may rest on the unexpanded surface <NUM> when being attached and therefore provide a good connection to this surface allowing a reliable connection thereto. The flanges may be attached to the unexpanded portion with spot welds at a number of locations along the length of the reinforcement flanges, although for instance a continuous weld or using a glue could be considered as other means for fastening the reinforcement beam. In between the flanges <NUM>, an intermediate portion <NUM> extends out of the plane of the flanges <NUM>. In the illustrated case, the intermediate portion <NUM> has the shape of a U or a truncated V with a flat bottom portion. Needless to say, other cross section shapes are conceivable where the intermediate portion extends out of the plane of the flanges <NUM> and provides an increased second area of moment. However, the illustrated shape may be well suited for serial production as will be shown, especially if the truncated bottom of the V-shape presents a surface at the same depth from the top surface of the shelf as does the U-shaped cross sections <NUM>, <NUM> of the side edges. Reinforcement structures with other shapes such as for instance a rectangular tube may be considered, or the top surface itself can be bent to form a reinforcement structure.

<FIG> shows a perspective view of a side piece <NUM> for a mesh shelf, and <FIG> shows an enlarged portion thereof. Once the main shelf piece is formed as illustrated in <FIG>, such side pieces may be fitted on the main piece short edges <NUM>, <NUM>, or more generally, on the edges parallel to the direction in which the main piece is expanded. In principle, those edges could be long edges with a different geometry. Such side pieces could be used also together with non-expanded main shelf pieces.

Although it is possible to provide each side piece as multiple parts, is advantageous to provide the side piece as a single piece of sheet metal which is bent into the configuration illustrated in <FIG>.

As shown in <FIG> each side piece comprises an inner part <NUM> with a C-shaped cross section presenting an upper, downward facing surface <NUM>, and a lower, upward facing surface <NUM>. The upper, downward facing surface <NUM> may be connected to the upper surfaces of the unexpanded main piece portion <NUM> and the edge portions <NUM>, <NUM>. A main piece of the shelf <NUM>, being fitted in the C-shaped configuration of the side piece <NUM> as illustrated in <FIG>, the main piece being seen from an edge portion <NUM>. It is possible e.g. to spot weld the side piece <NUM> to the main piece at those locations. The lower, upward facing surface <NUM> may similarly be connected to the lower surfaces presented by the U-shaped cross sections <NUM>, <NUM> bent at the long edges of the main piece, and to the bottom of the reinforcement beam <NUM>. In addition to spot welding, other fastening techniques are conceivable such as continuous welding, soldering or gluing.

The side piece <NUM> may also comprise and outer part <NUM> that is bent from the inner part and presents a downwards directed flange <NUM>. This flange <NUM>, may be used to attach the shelf to a bracket (not shown) in order to suspend the shelf therefrom. Such brackets, presenting a U-shaped cross section to which the shelf may be attached, can be attached in a cantilevered fashion from a carrier element which is attached to a wall or the like, and are well known per se.

As illustrated, the side piece <NUM> may comprise a front tongue <NUM>, which is folded over the end of the downwards directed flange <NUM> and prevents the flange from sliding in a bracket of the above-mentioned type. As shown, the lower <NUM> end of the downwards directed flange <NUM> may be angled slightly outwards to facilitate the fitting or the shelf in a bracket. Such side pieces <NUM>, may be fitted to both short ends of the main piece to cover the ends of the expanded portions <NUM>, <NUM>, and to allow the shelf to be suspended from brackets or the like.

<FIG> illustrate schematically other configurations of a mesh shelf surface. As illustrated, it is possible to provide more expanded areas <NUM> and more unexpanded areas <NUM> on a shelf top surface. <FIG> illustrates an example with two unexpanded areas <NUM> located at approximately <NUM>/<NUM> and <NUM>/<NUM> of the depth of the shelf, while <FIG> illustrates an example with three unexpanded areas located at approximately <NUM>/<NUM>, <NUM>/<NUM>, and <NUM>/<NUM> of the depth of the shelf. Reinforcements <NUM> (cf. <FIG>) may be located beneath all or some of the unexpanded areas along their whole lengths or parts thereof. Expanded areas are located in between the unexpanded areas and run all the way from side piece <NUM> to side piece <NUM> as the main piece (cf. <FIG>) is expanded across its whole surface to remain flat.

Needless to say, other configurations may be considered, and although the configurations in <FIG>, <FIG> are symmetrical with respect to the mid-point of the shelf's depth, this is not necessary.

Claim 1:
A partly expanded sheet metal shelf (<NUM>) for a storage system, the shelf comprising a top surface including an area (<NUM>, <NUM>) with an expanded metal mesh panel wherein the metal mesh panel being provided in two bands along the sheet metal, made with a number of small, parallel slits, running in successive parallel rows, by punching and expanding in a direction perpendicular to the slits, forming a rhombus-shaped small opening at the location of each slit, the shelf comprising at least one unexpanded area (<NUM>), provided by not punching slits in that portion of the sheet metal, in between the two expanded (<NUM>, <NUM>) areas, along the shelf, the shelf further comprising a reinforcement (<NUM>), which reinforcement is arranged at a bottom side of the shelf top surface, the reinforcement (<NUM>) having flanges (<NUM>) adapted to facilitate fastening to the unexpanded area (<NUM>) at the lower surface thereof.