Modular Rack System for Use With Removable Pans

1. Field of the Invention

The present invention relates generally to modular rack systems. More particularly, the present invention relates to an improved "knockdown" modular, vertical, formed-wire rack system, which is especially well suited for commercial use with conventional removable pans for holding items, such as commercial bakery products, and which may be readily assembled and disassembled without tools to facilitate shipping, storing, and cleaning.

Although the rack system of the present invention is especially well-suited for use with removable pans for holding baking products in the food service industries, it can be used with equal advantage in combination with a variety of generally flat trays or the like, in many other commercial, industrial and residential applications and environments.

2. Description of the Prior Art

Modular shelving systems are well known. For example, U.S. Pat. Nos. 3,138,123 (Maslow) and 3,208,408 (Maslow) disclose knockdown shelving units that have achieved great commercial success under the trademark ERECTA SHELF of Applicant's Assignee, InterMetro Industries Corporation.

U.S. Pat. No. 3,523,508 (Maslow) discloses a modular adjustable shelving system that has also achieved great commercial success under InterMetro Industries' trademark SUPER ERECTA SHELF. This system comprises a formed-wire shelf component having a frusto-conically-shaped collar at each corner for receiving a support post. Each collar tapers outwardly toward its lower extremity when viewed in normal use. Generally cylindrical support posts, each having a plurality of uniformly spaced annular grooves formed in its outer surface, are secured to the shelf by means of a mounting assembly. Each mounting assembly comprises at least two separate, complementary, conical-shaped mounting members which are joined about and at least partially surround the support posts to define a sleeve. The outer surface of each sleeve is frusto-conically shaped and its inner surface is generally shaped as a right, circular cylinder. Thus, the mounting member is thickest at its bottom. The sleeves are sized to fit snugly within the shelf collars. A rib formed on an inside surface of each sleeve is sized to engage the grooves formed in the support post.

In use, sleeves are first placed about each support post such that the rib formed on the inside surface of each sleeve engages an appropriate groove in the support post at the desired height. The support posts with the sleeves mounted thereon are then each passed through one respective collar at a corner of each shelf. The collars, sleeves, and posts firmly engage each other due to their relative respective sizes. When all support posts are inserted, the shelving system is placed in position and is ready for use. As the load on the shelf increases, a radially-inwardly directed force between the collars and sleeves brings the sleeves into locking relation with the posts due to the wedging action between the collars and sleeves.

U.S. Pat. No. 3,757,705 (Maslow) discloses an adjustable shelving system similar to U.S. Pat. No. 3,523,508.

Other examples of known shelving systems are disclosed in U.S. Pat. Nos. 3,316,864 (Maslow); U.S. Pat. Nos. 4,629,077 (Niblock); 4,799,818 (Sudimak, et al.); 4,811,670 (Kolvites, et al.); 4,892,044 (Welsch); 4,964,350 (Kolvites, et al.); and 4,989,519 (Welsch, et al.).

Although the foregoing shelving systems are well suited for many varied applications, there is a need for a formed-wire modular knock-down rack system using the structural principles, for example, of the Maslow or Kolvites Patents, but that also is particularly well adapted for use in the baking industry. Such a rack system should allow baked products such as bread, buns, rolls, and the like, to be removed from the oven, still hot and on their baking pans, and to be supported by the rack system. Individual pans could be inserted and removed from the rack system as required. Ideally, the rack system should be constructed to be as open as possible to allow for maximum ventilation so that freshly baked products can quickly cool to room temperature for further handling as need be. Moreover, the open construction of the rack system should minimize the surface area of the rack system thereby facilitating cleaning and maintaining sanitary conditions. Further, the rack system should be fabricated from materials which are not adversely affected by high temperatures and which resist corrosion and contamination by food particles, dust, and the like.

U.S. Pat. No. 4,004,819 (Brongo) discloses a mobile truck having removable racks for pans, trays and the like that achieves many of the objectives noted above but may not be completely and easily knocked down for shipment and storage as is desirable. Therefore, still further improvements are possible.

It is an object of the present invention to improve upon the structural concepts of the modular shelving systems known in the prior art and adapt such improvements particularly to modular rack systems.

It is another object of the present invention to provide an inexpensive, knockdown, modular rack system that can be readily assembled and disassembled with minimal effort and without tools yet still has high strength, stability, and rigidity.

It is still another object of the present invention to provide a substantially open, formed-wire rack system which is aesthetically pleasing, simply fabricated, stable in use, corrosion-resistant and readily cleaned.

It is another object of the present invention to provide an inexpensive, formed-wire rack system that is adapted to removably support a plurality of conventional baking pans which can be individually inserted and removed.

In a preferred embodiment the invention is a rack system that includes a horizontal base frame assembly, a horizontal top frame assembly, and a pair of opposed vertical support assemblies. Each vertical support assembly comprises a plurality of spaced vertical support rods and a plurality of spaced horizontal support brackets or rails secured to the vertical support rods at points where they intersect each other. At least two of the vertical support rods engage and interlock with the base frame assembly and the top frame assembly such that each vertical support assembly is restricted from movement relative to said base frame assembly and the top frame assembly in first and second directions. The plurality of support brackets are arranged in substantially co-planar facing pairs to support a removable pan between the pair of vertical support assemblies.

In accordance with further features of the preferred embodiment, the invention pertains to a rack system that includes a horizontal base frame assembly, a horizontal top frame assembly, a pair of opposed vertical support assemblies, and a plurality of support posts. Each vertical support assembly includes a plurality of spaced support rods and a plurality of spaced support brackets secured to the support rods at the points where they intersect each other. At least two of the support rods engage and interlock with the base frame assembly and the top frame assembly such that each vertical support assembly is restricted from movement relative to the base frame assembly and the top frame assembly in first and second directions. The plurality of support posts are disposed between and removably secured to the base frame assembly and the top frame assembly so as to further restrict relative movement therebetween. The plurality of support brackets are arranged in substantially co-planar facing pairs to support a removable pan between the pair of vertical support assemblies.

A more complete appreciation along with an understanding of other aspects, objects, features, and advantages of the present invention will become apparent from the following detailed description, when considered in conjunction with the accompanying drawings.

FIG. 1 is a fragmented, perspective view of an assembled modular rack system for use with removable pans, constructed in accordance with a preferred embodiment of the present invention.

FIG. 2 is an outside, front elevational view of the assembled rack system shown in FIG. 1.

FIG. 3 is a fragmented, right-side elevational view of a vertical support assembly including a plurality of horizontal support brackets with several baking pans supported thereon, used in the rack system shown in FIG. 1.

FIG. 4 is a top plan view of a frame assembly, used in pairs as a base and a top, respectively, of the rack system shown in FIG. 1.

FIG. 5 is a front elevational view of the frame assembly shown in FIG. 4.

FIG. 6 is a right-side elevational view of the frame assembly shown in FIG. 4.

FIG. 7 is a fragmented, partial-sectional view illustrating a detail of the frame assembly shown in FIG. 4.

FIG. 8 is a view of a mat assembly which, when properly bent, forms a support rack that is a major component of the vertical support assembly of the rack system shown in FIG. 1.

FIG. 9 is a fragmented, top plan view of the mat assembly shown in FIG. 8 after being properly bent to form a support rack.

FIG. 10 is a fragmented, partial-sectional, top plan view illustrating the positional relationship of the frame assembly shown in FIG. 4, and the support rack shown in FIG. 9.

FIG. 11 is a fragmented, perspective view showing the positional relationship of the frame assembly depicted in FIG. 4, and the support rack shown in FIG. 9.

FIG. 12 is a vertical elevational view of a pan stop assembly used with the support rack shown in FIG. 9 which in combination form the vertical support assembly of the rack system shown in FIG. 1.

FIG. 13 is a fragmented, partial-sectional top plan view of the pan stop assembly shown in FIG. 12 connected to the support rack shown in FIG. 9.

FIG. 14 is a fragmented, elevational view of a support post used in the rack system shown in FIG. 1.

FIG. 15 is a fragmented, perspective view of a corner of the frame assembly shown in FIG. 4 and the support post shown in FIG. 14 with a leveling device inserted therein.

Initially, for purposes of explanation, the attitude and location of components of the rack system of the present invention will be defined with reference to a fully assembled system when viewed in normal use. Accordingly, the term "horizontal" refers to a direction parallel to a surface on which the fully assembled rack system is supported in normal use. Similarly, the term "vertical" refers to a direction substantially perpendicular to the horizontal direction. "Base" refers to the end of the rack system closest to the surface on which the rack system is supported, and "top" refers to the opposite end. The "front" and "rear", "left side" and "right side" of the rack system are relative terms as will be defined below.

FIG. 1 illustrates a preferred embodiment of the rack system 1. For purposes of explanation, reference numerals 10, 11, 12 and 13 respectively designate left-front, right-front, left-rear and right-rear corners of the rack system 1. While the system 1 will be described in detail below, it generally comprises a first polygonal frame assembly 2 serving as a base, and a second identical frame assembly 2' serving as a top, a first vertical support assembly 4, a second vertical support assembly 4' and a plurality of support posts 8.

The first vertical support assembly 4 is disposed on one side of the rack system 1, and the second opposing vertical support assembly 4' is disposed in mirror-image relationship, on the opposite side of the rack system 1. The vertical support assemblies 4,4' are fabricated to include a plurality of spaced horizontal support brackets or rails 30, 32 and 34 for supporting, for example, baking pans (not shown), or the like between the two opposing vertical support assemblies. A pair of spaced vertical stop rods 52 are provided in the vertical support assemblies 4,4' to prevent the baking pans from slipping off the support brackets 30, 32. Projecting end portions of a plurality of spaced vertical support rods 42, 44 and 46 provided at each corner of the vertical support assemblies 4,4' engage and interlock with side trusses and certain cross braces of the base and top frame assemblies 2,2' respectively, of the rack system 1 with an interference-fit or friction-fit.

A frustoconical collar 6 of the type described in U.S. Pat. Nos. 3,523,508 and 3,757,705 (both to Maslow), which are incorporated herein by reference, is provided at each corner of the base and top frame assemblies 2,2'. Each collar 6 receives a split frustoconical sleeve 6', also of the type described in the Maslow Patents, that may be removably secured to a support post 8. Thus the support posts can support the frame assemblies through the intermediary of the split sleeves as described in those patents. If desired, casters 7 or levelling devices (not shown in FIG. 1) may be attached to the support posts 8 to facilitate the positioning of the rack system 1.

FIG. 2 shows a front of the rack system 1 as viewed from the outside of the vertical support assembly 4 toward the interior of the system in the direction of vertical support assembly 4'. Since the vertical support assembly 4' is identical to the vertical support assembly 4 and is positioned in mirror-image relation to the support assembly 4, the view from the other side of the rack system 1 is substantially identical. Baking pans 100 are removably supported on the inwardly directed support rails 30, 32 between the vertical support assemblies 4, 4' and may be inserted and removed in the direction shown by the two-directional arrow. Since vertical support assembly 4' is identical to vertical support assembly 4, only the former will be described in the interest of simplicity.

At each bottom corner of the vertical support assembly 4, it will be seen that a projecting portion at each end of vertical support rods 42 extends alongside an outboard side of an upper rib 14 and lower rib 16 of frame assemblies 2,2'. In addition, a projecting portion at each end of vertical support rods 44 extends alongside an inboard side of the upper rib 14, and the lower rib 16, and alongside an outboard side of cross braces 26 of frame assemblies 2,2' shown in FIG. 2 and 4. Projecting portions at each end of vertical support rods 46 also engage cross braces 26 but cannot be seen in FIG. 2. The combination of these projecting end portions of the vertical support rods 42, 44 and 46 with ribs 14 and 16 and cross braces 26 provide an interference fit of the vertical support assemblies 4, 4' with frame assemblies 2,2'.

FIG. 3 shows a fragmented, right side elevational view of the vertical support assembly 4 including horizontal support brackets 30, 32 and 34 which are welded at the points at which they intersect vertical support rods 42, 44 and 46. Horizontal rods 56, shown in section, comprise components of the pan stop assembly 5, which will be discussed later in detail. A number of baking pans 100 are removably supported on support brackets 30 and 32.

Referring now more specifically to FIGS. 4 through 7, in a preferred embodiment of the invention, both frame assemblies 2,2' are generally rectangular and have a relatively long dimension running along the front and back, and a relatively short dimension running along the left and right sides of the rack system 1. A typical frame assembly may be approximately 261/2".times.21".times.11/2". Of course, many other sizes are possible. The rectangular shape is advantageous since readily available, commercial baking pans also are generally rectangular in shape. Other shapes of rack systems, such as trapezoidal, triangular, and the like, also are possible. However, the use of such shapes would require the use of similarly shaped baking pans which may have to be custom made and which likely would be more expensive than the rectangular-shaped pans.

As noted, both frame assemblies 2,2' have a frusto-conical collar 6 disposed at each corner. Each of the collars 6 is arranged so as to taper outwardly toward its lower extremity when the rack system 1 is positioned in normal use. The collars 6 may be fabricated from cold rolled steel or stainless steel although any formable metal may be used. Two pairs of cross braces 26, 28 and a pair of V-shaped braces 27 are provided to stiffen each of the frame assemblies 2,2' Four snake-like trusses, along with the collars 6, define the perimeter of the frame assemblies 2,2'.

The two-directional arrow shown in FIG. 4 illustrates the baking pan loading and unloading directions for an end-loading rack system.

With reference to FIG. 5, a first pair of the snake trusses which form the front and back of the frame assemblies 2, 2' now will be discussed. The upper rib 14 and an equal length lower rib 16, formed, for example, from 1/4 inch bright basic steel (B.B.S.) wire are welded at both ends to the collars 6 at the left-front corner 10 and the right-front corner 11. A continuous, snake-like rib 18 formed, for example, from number 7 American Wire Gage (AWG) B.B.S. wire is sized so as to fit between the upper and lower ribs 14 and 16 and is welded at the points where it comes in contact with the upper and lower ribs. Of course, many other wire sizes may be used to form the snake trusses depending on material cost, availability, the intended loading of the rack system, etc.

Resistance welding preferably may be used to attach the several components of the rack system. Other forms of attaching the components may be used, such as oxyacetylene gas welding, brazing, and the like. However, resistance welding is fast and very strong, and it does not greatly upset the work which results in readily made, very secure, smooth weld connections. Moreover, resistance welding is especially well suited to connect intersecting wire rods. However, in some instances, such as where the ribs are secured to the collars 6, other-forms of welding may be preferred to provide a smooth contour at the weld joint.

The snake trusses function as stiffener trusses at the front and back of the frame assemblies 2,2', respectively.

Next, a second pair of snake-like trusses which form the left side and the right side of frame assemblies 2,2' will be discussed with reference to FIG. 6. Each of the second pair of snake trusses comprises an upper rib 20 and an equal length, lower rib 22, both being somewhat shorter than upper and lower ribs 14 and 16, respectively. Ribs 20 and 22 also are preferably made of 1/4 inch wire and are welded to the collars 6 substantially perpendicular to upper and lower ribs 14 and 16. Another continuous snake-like rib 24, also preferably made of number 7 AWG B.B.S. wire, is sized to fit between the upper rib 20 and lower rib 22 and is welded at the points where it comes in contact with the upper and lower ribs. Again, of course, many other wire sizes may be used to form the above-mentioned components as circumstances require.

This pair of snake trusses also function as stiffener trusses at the left and right sides of the frame assemblies 2,2', respectively.

Thus, the front and back snake trusses are disposed substantially perpendicular to the left and right side snake trusses and in cooperation with the collars 6 at the vertices, define the perimeter of the frame assemblies 2,2'.

Again referring to FIG. 4, a first pair of frame assembly cross braces 26, also preferably formed of 1/4 inch B.B.S. wire, are disposed substantially perpendicular to the front and back snake trusses. The cross braces 26 are welded to the underside of the upper ribs 14 at the points where they intersect each other.

A second pair of frame assembly cross braces 28, also preferably formed of 1/4 inch B.B.S. wire, are welded to the underside of upper ribs 20 at the points where they intersect each other.

As shown in FIG. 7, the cross braces 28 are offset by an amount "d", which is approximately equal to the diameter of the wire used for cross braces 26, at a distance "a" approximately 3 inches from each end of cross braces 14. Cross braces 26 are disposed at a distance "b" approximately 11/2 inches from each end of cross braces 28. The offset allows the cross braces 28 to be secured to the underside of upper ribs 20 and still clear the top of cross braces 26. In addition, the offset ensures that the middle portions of the cross braces 28 are substantially co-planer with the upper ribs 14 of the frame assemblies 2,2'. The bottom of the cross braces 28 are welded to the top of the cross braces 26 at the points where they intersect each other in order to increase the rigidity of the frame assemblies 2,2'.

In addition, the pair of V-shaped braces 27 are welded at two points near their respective vertices at the points where they intersect the underside of the upper ribs 14. The V-shaped braces 22 are welded at the ends of their respective legs to the underside of the cross braces 26 at the points where they intersect each other. To further stabilize the frame assembly 2,2', the tops of the V-shaped braces 27 also are welded at the points where they intersect the underside of the cross braces 28.

As illustrated in the drawing figures, the rack system 1 is adapted for "end loading". Stated differently, removable pans 100, trays, and the like, may be inserted or removed from both the right and left sides of the rack system 1 as suggested by the bidirectional arrow. Alternatively, the rack system also may be arranged as a "front loading" unit, that is as a rack system which permits insertion and removal of the baking pans 100 from the front and back. To effect such an arrangement, the vertical support assemblies 4,4' are disposed so as to engage and interlock with the left and right sides of the frame assembly. Cross braces 28 must be offset to clear cross braces 26. Similarly, the welding points of cross braces 26, 28 and V-shaped braces 27 will change accordingly.

As noted above, the top frame assembly 2, is identical to base frame assembly 2. Consequently, its construction need not be separately discussed.

FIG. 8 illustrates a view of a mat assembly blank from which a horizontal pan support rack 3 maybe fabricated. The term "blank" means that the figure shows the component prior to final bending during its fabrication. In other words, it shows the horizontal pan support rack 3 in a substantially flat state. Subsequent figures of the drawing illustrate the final shape of the horizontal pan support rack 3 after being properly bent. Each vertical support assembly 4 and 4' is made up of a properly bent horizontal pan support rack 3 and a pan stop 5 assembly to be discussed in greater detail hereinbelow.

Each horizontal pan support rack 3 comprises a plurality of spaced horizontal support brackets or rails, including a base support bracket 30, a plurality of intermediate support brackets 32, and a top support bracket 34. The support brackets 30, 32 and 34 are identical but for their position in the rack system 1. In a preferred embodiment, the support brackets are formed of number 7 AWG B.B.S. wire. In addition, each horizontal pan support rack 3 comprises a plurality of spaced vertical support rods 42, 44 and 46, which are also identical but for their position in the rack system. Preferably, the vertical support rods 42, 44 and 46 are formed of 1/4 inch B.B.S. wire. The support brackets 30, 32 and 34 are welded near their respective end portions at the points where they intersect the vertical support rods 42, 44 and 46.

In a typical configuration, twenty support brackets are arranged in parallel, approximately 3 1/32 inches on center, resulting in a horizontal pan support rack 3 having nineteen baking pan spaces, and standing approximately five feet tall.

The vertical support rods 42 and 44 are disposed such that when the horizontal pan support rack 3 is properly formed, end portions of the vertical support rods will engage and interlock with inboard and outboard surfaces of portions of the upper and lower ribs 14 and 16 of the front and back snake trusses of the frame assemblies 2,2' for an end loading rack system. Alternatively, the end portions of vertical support rods 42 and 44 may be disposed to engage inside and outside surfaces of portions of the upper and lower ribs 20 and 22, respectively, of the left and right trusses of base and top frame assemblies 2,2' for a front loading rack system.

It will be understood that the dimensions of the base and top frame assemblies and vertical support assemblies must be such so as to allow proper engagement as described herein. The width of the vertical support assemblies 4,4' is generally sized to be approximately equal to the dimension defined by the length of the cross braces 28 between the cross braces 26 for an end loading unit, or the dimension defined by the length of the cross braces 26 extending between the cross braces 28 for a front loading unit.

FIG. 9 shows a fragmented top view of a mat assembly after it has been formed into a horizontal pan support rack 3, being generally C-shaped and having a short turned-in portion at either end.

Square bends are used to form each corner of the support brackets 30, 32 and 34 such that they are generally rectangular.

FIGS. 10 and 11 show the positional relationship of one end of horizontal pan support rack 3 and a left-front corner 10 of the base frame assembly 2. Projecting portions of the vertical rods 42 and 44 extend on opposite sides of a portion of the front snake truss formed by the upper rib 14, the lower rib 16 and the snake-like rib 18. The spacing between the vertical rods 42 and 44 is substantially equal to the diameter of the upper and lower ribs 14,16. Thus, a snug or embracing engagement with the front snake truss of the base assembly 2 is established. A similar arrangement is established at the other end of the horizontal pan support rack 3 with respect to another section of the front snake truss of the base assembly 2. Consequently, movement in a first direction, of the vertical assembly 4 relative to the frame assembly 2 is restricted.

The projecting portions of vertical rods 46 together with the projecting portions of rods 44 are disposed outbound of frame cross braces 26 at each side of the base frame assembly 2. The bottom support bracket 30 is arranged such that the distance "c" shown in FIG. 9 between rods 44 and 46 on opposite ends of the vertical support structure is substantially equal to the distance between the cross braces 26 plus an amount equal to two diameters of the wire used to form the cross braces 26. Thus, a snug or embracing fit is formed around frame cross braces 26. A similar arrangement, in mirror-image is established at the other end of the horizontal support pan support rack 3. Consequently, movement of the vertical support assembly 4 is restricted relative to the base frame assembly 2 in a second direction substantially perpendicular to the first direction. In addition, the bottom of support bracket 30 is supported in the vertical direction by the top of upper rib 14 and cross braces 28.

The top frame assembly 2' is arranged relative to the vertical assemblies 4,4' in a manner substantially similar to that of the base frame assembly 2. However, when the top frame assembly 2' engages the vertical support assemblies 4,4', the lower rail 16 of the top frame assembly 2' captures the top surface of support bracket 34 in the vertical direction.

The other corners 11, 12 and 13 of the base and top frame assemblies engage the vertical support structures in a manner similar to that shown in FIGS. 10 and 11 for the left-front corner 10, and need not be individually discussed.

FIG. 12 shows a pan stop assembly 5 comprising a plurality of spaced vertical stop rods 52 and a plurality of spaced horizontal stiffener rods 56, all formed, for example, of 1/4 inch B.B.S. wire. Each end of the horizontal stiffener rods 56 is welded to the vertical support rods 46 of the lateral pan support rack 3, which are shown by phantom lines. When a pair of pan stop assemblies 5 is welded, respectively, to a pair of horizontal pan support racks, they form a pair of vertical support structures 4, 4'. The pan stop assembly 5 prevents the baking pans 100 which are placed on the support brackets 30, 32 from slipping through the front and back of the rack system 1 in an end-loading arrangement. Similarly, when a pair of the pan stop assemblies 5 and vertical support structures 4,4' are disposed on the left and right sides of the rack system 1, the baking pans 100 will be prevented from slipping from a front-loading arrangement.

The pan stop assemblies 5 also add rigidity to the rack system 1, and in particular to the vertical support assemblies 4,4'.

FIG. 14 shows a fragmented support post 8. As noted generally above, a plurality of circumferential grooves 62 are formed at each end of the support post 8. These grooves are provided to receive the ribs formed on an inside surface of a supporting frusto-conical sleeve (not shown in FIG. 4) such as that described in U.S. Pat. Nos. 3,523,508 and 3,757,705. (Both to Maslow), which is also incorporated herein by reference.

In addition, a plurality of grooves 66 are formed approximately in the middle of each of the supporting posts 8. These middle grooves 66 are generally cosmetic and are not necessary to the construction of the invention. However, they do serve as a convenient indication of the approximate center of balance of the unloaded rack system 1. In addition, they provide a better grip for positioning the rack system 1. Both of these aspects facilitate moving the rack system 1.

The support posts 8 are generally hollow and are typically made of metal, most preferably bright zinc plated cold-rolled steel or stainless steel sheet. These compositions are relatively lightweight, provide high structural rigidity, and are inexpensive to manufacture by known metal forming methods. Further, these materials are resistant to corrosion and are easily cleaned. Still further, the grooves 62 and 66 may be efficiently formed therein, using known metal forming methods such as rolling.

Alternatively, the support posts 8 may be made of any conventional material which can be formed to define the above features, particularly including materials such as plastics. Such alternative materials may be well suited to particular rack system applications. Further, the support posts 8 may be solid.

FIG. 15 illustrates another embodiment of the rack system featuring a vertically adjustable leveling assembly 60 shown at the left-front corner assembly 10 of the rack system 1. The leveling assembly 60 comprises a foot portion 62 and a threaded portion 64. The threaded portion 64 engages a thread-receiving portion (not shown) which is secured, or otherwise formed, in an end of each support post 8 which is inserted in a collar 6 of the base and top frame assemblies 2,2'.

In order to assemble the rack system, four support posts are first each equipped with one frustoconical sleeve 6' that collectively are located on the posts at uniform height. Then the bottom frame assembly 2 is mounted on the four posts with a collar 6 at each corner of the frame assembly receiving one sleeve. The projecting portions of the vertical support rods 42, 44 and 46 of one end of a first vertical support assembly 4 are positioned so as to engage the appropriate snake truss and cross brace of the bottom frame assembly. When done properly, the projecting portions of the vertical rods 42, 44, 46 at each end of the first vertical support assembly will hold the vertical support assembly in a vertical position when the bottom frame assembly 2 is supported through the collars and sleeves on the four support posts. The second vertical support assembly 4' is positioned so as to engage an opposing side of the bottom frame assembly 2 and it too will be maintained in an upright position. Next sleeves are mounted at the tops of each of the posts again collectively at a uniform height in the region where the top frame assembly 2' is to be mounted. Then the top frame assembly 2' is positioned over the top of the two vertical front assemblies 4,4' with its respective collars receiving the associated sleeves so that the top frame assembly can be pressed down on the top projecting portions of the vertical rods 42, 44 and 46 to capture them. When so assembled, the vertical frame assemblies 4,4' are restricted from movement relative to the frame assemblies 2,2' in two directions as the result of the interlocking arrangement of projecting portions of the vertical rods, snake trusses and cross braces. At this point, the rack system is capable of maintaining a free-standing state.

If desired, casters 7 or leveling assemblies 60 can be secured in the bottom of each support post 8.

The rigidity of the rack system 1 is increased by inserting downward pressure on the base and top frame assemblies 2,2'. As noted previously, the load on the rack system in normal use also adds to the rigidity and stability of the rack system. The system 1, thus configured, is now ready to be positioned and to receive one or more baking pans 100 which will be supported at each end by the top surface of common-height pairs of the brackets 30, 32 between the vertical support assemblies 4, 4'.

While corner post, shelf collar, and sleeve configurations such as are shown in U.S. Pat. Nos. 3,523,508 and 3,757,705 have been described in connection with one preferred embodiment, other corner post configurations adapted to support the top and bottom frames may be provided.

It will be appreciated that the present invention provides many improvements over known shelving systems in that it is particularly well adapted to support pans or trays in a convenient, low cost manner.

Thus, what has been described is an inexpensive, stable, light-weight vertical rack apparatus capable of bearing a great deal of weight, and capable of being very easily assembled. Those having skill in this field will readily appreciate the economic advantages accruing to such a design.

Of course, all specific shapes, dimensions, wire sizes and materials mentioned herein are provided by way of example only. Rack systems fabricated in shapes, dimensions and using different wire sizes and materials other than those discussed herein also are contemplated.

Although specific embodiments of the present invention have been described above in detail, it will be understood that this description is merely for purposes of explanation. Various modifications of and equivalent structures corresponding to the disclosed aspects of the preferred embodiments in addition to those described above may be made by those skilled in the art without departing from the spirit of the present invention which is defined in the following claims, the scope of which is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures.