Abstract:
A collapsible and stackable pallet rack is provided for shipping and storing heavy roll goods having a central mandrel. The rack includes two pairs of adjacent and opposite upright corner posts being foldable inwardly and downwardly. Two side bars connect together the pair of opposite upright corner posts. There are also two pairs of upper and lower end bars. Each pair of end bars connect together one pair of adjacent upright corner posts. On top of each upper end bar, there is one cradle positioned centrally thereon for receiving one end of the central mandrel. A holddown plate is fastened on top of each cradle. Two pairs of hinge plates connect the two pairs of corner posts with the two side bars. This rack provides a shipping unit that prevents damage to heavy roll goods during transit and simultaneously provides a cost-effective stackable storage unit.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to collapsible pallet racks and more particularly to a collapsible and stackable steel rack for shipping and storing heavy roll goods. 
     2. Description of the Related Art 
     Collapsible steel pallet racks were first developed in the late 1950s by the Clark Equipment Co. of Battle Creek, Mich., to replace wooden pallets for storing and transporting heavy awkward articles, such as automobile engines. An exemplary prior art steel pallet is shown in U.S. Pat. No. 2,956,763 which issued on Oct. 18, 1960, to Nicholas D&#39;Arca. 
     During the 1960s, the textile industry developed various heavy duty, strong racks for yarn-carrying beams. Examples are given in U.S. Pat. No. 3,084,803 which issued to Bayers on Apr. 9, 1963; in U.S. Pat. No. 3,355,029 which issued to Eurey on Nov. 28, 1967; and in U.S. Pat. No. 3,430,773 which issued to Hancock on Mar. 4, 1969. 
     During the 1970s, improved foldable shipping racks for heavy items, such as automobile engines, were developed in both the United States and Japan. Such racks are shown in U.S. Pat. No. 3,804,033 which issued to Izawa et al. on Apr. 16, 1974, and in U.S. Pat. No. 4,098,409 which issued to Massey on Jul. 4, 1978. These developments were satisfactory to carry industry through the 1980s. 
     However, during the 1990s, a need developed for more durable, reusable, foldable, transporting and packaging racks for mechanically sensitive goods in the form of large rolls. This need was met by various racks manufactured in both the United States and Germany. Such racks are illustrated by U.S. Pat. No. 5,228,821 which issued to Gleffe et al. on Jul. 20, 1993; U.S. Pat. No. 5,242,255 which also issued to Gleffe et al. on Sep. 7, 1993; U.S. Pat. No. 5,692,625 which issued to Filipescu et al. on Dec. 2, 1997; and U.S. Pat. No. 5,941,398 which issued to Harris on Aug. 24, 1999. 
     SUMMARY OF THE INVENTION 
     A primary object of the present invention is to provide a collapsible and a stackable pallet rack with a hinged arrangement that allows the rack to fold inwardly and downwardly at its sides. This rack provides a shipping unit that prevents damage to heavy roll goods during transit and simultaneously provides a cost-effective stackable storage unit. 
     A secondary object of the present invention is to provide a cradle that includes a holddown plate which prevents a mandrel from accidently coming off during transit. The cradle has a deep inset and the holddown plate are innovative to collapsible pallet racks. Thus, the present invention returns freight shipping efficiencies not obtainable with prior art devices. 
     A tertiary object of the present invention is to use cotter pins to secure upright corner posts in the rack. Such cotter pins are placed above the hinges and are included as a basic safety feature. Another safety feature is the use of trapezoidal foot plates reinforced with seven-gauge angle iron to provide added strength in stacking the racks in a nesting arrangement. 
     In summary, the present invention is a pallet formed of steel in a manner like no other in the industry. It should provide manufacturers and users of large volume papers and films with an economical way to handle a reusable product. Furthermore, the present invention is intended to replace the use of end boards, wooden pallets and cardboard or plastic core plugs that have a limited life and perform only marginally in protecting large product rolls during shipment and storage. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the invention. 
     FIG. 2 is a partial lower end view taken along line  2 — 2  of FIG.  1 . 
     FIG. 3 is a top plan view of the invention. 
     FIG. 4 is a side elevational view taken along line  4 — 4  of FIG.  1 . 
     FIG. 5 is an end view of the invention in use. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In FIG. 1, a stackable pallet rack  10  is made of steel and is shown in its uncollapsed position. The rack  10  has two pairs of upright corner posts  12 A and  12 D which are foldable inwardly and downwardly in a direction of arcuate arrows A. Two long side bars  14  connect opposite corner posts  12 A and  12 D at their bottom ends  12 B. Each of the corner posts  12 A and  12 D has an upper end  12 F which sits in each bottom end  12 B at a seam  12 G. A pair of short upper end bars  16 A connects adjacent pairs of corner posts  12 A and  12 D together at their vertical centers  12 C while a pair of short lower end bars  16 B connects the same adjacent posts  12 A and  12 D together at their bottom ends  12 B. Two long middle bars  18  run parallel to the two long side bars  14  and connect opposite lower end bars  16 B together. A plurality of short cross braces  20  connects each middle bar  18  to its adjacent side bar  14  while at least one middle brace  22  connects the two middle bars  18  together at their centers  18 C. Together, the two long side bars  14 , the two long middle bars  18 , the plurality of short cross braces  20  and at least one middle brace  22  form a rigid bed-like structure like no other in the industry. A pair of hinge plates  24 A connects the pair of corner posts  12 A to one end  14 A of the side bars  14  while another pair of hinge plates  24 B connects the pair of corner posts  12 D to another end  14 B of the side bars  14 . A pair of trapezoidal foot plates  26 A receives the bottom ends  12 B of the one pair of corner posts  12 A while another pair of trapezoidal foot plates  26 B receives the bottom ends  12 B of the opposite pair of corner posts  12 D. A pair of brackets  28 A is secured below each of the lower end bars  16 B while another pair of brackets  28 B is secured below each side bar  14 . The brackets  28 A and  28 B receive prongs of a forklift (not shown) to allow an operator to lift a rack  10  safely. Thus, because the brackets  28 A and  28 B are located on all sides of the rack  10 , the forklift operator may enter the rack  10  in any one of four directions to remove the rack  10  from a stack thereof. Each of the corner posts  12 A and  12 D has a top end pin  12 E which projects into an underside of each of the foot plates  26 A and  26 B of another rack (not shown) placed on top of the rack  10  to build a stable stack. A rectangular box  30  is mounted on top of each lower end bar  16 B near to the bottom end  12 B of one of the posts  12 A and one of the posts  12 D. These boxes  30  aid in preventing a large roll (not shown) from shifting in the rack  10 . A cradle  32  is positioned on top of each upper end bar  16 A at their horizontal centers  16 C. A holddown plate  34  is fastened on top of each cradle  32  to prevent a central mandrel (not shown) of a large roll (also not shown) from jumping out of the cradle  32  in the event that the rack  10  would receive a strong shock from an external force, such as a forklift or an earthquake. A name plate  36  may be provided along the side bar  14  to identify either the manufacturer or the owner of each rack  10 . 
     FIG. 2 is a lower end view of the rack  10  taken along line  2 — 2  of FIG.  1 . FIG. 2, the corner posts  12 D are joined at their bottom ends  12 B by the lower end bar  16 B. The corner posts  12 D sit in the pair of trapezoidal foot plates  26 B. The ends  14 B of the side bars  14  (not shown) are seen in phantom lines. Likewise, ends  18 B of the middle bars  18  (not shown) are illustrated in phantom lines. The brackets  28 A and the boxes  30  are seen below and above, respectively, the end bar  16 B. Also, the placement of the upper ends  12 F into the bottom ends  12 B of the corner posts  12 D at the seam  12 G is clearly shown. Bore holes  12 H are drilled in alignment with each other at a top of each bottom end  12 B and in a mating block  12 J of each upper end  12 F of the corner posts  12 D so that a cotter pin (not shown) may be pushed therethrough to secure the upper end  12 F to the bottom end  12 B of each corner post  12 D at the seam  12 G. 
     In FIG. 3, a top plan view of the rack  10  is shown with the corner posts  12 A and  12 D, each having the top end pin  12 E. The trapezoidal foot plates  26 A and  26 B are made of seven-gauge angle iron. The upper end bars  16 A connect each adjacent pair of corner posts  12 A and  12 D together. The side bars  14  connect one corner post  12 A to the opposite corner post  12 D. The pair of middle bars  18  extends parallel to the side bars  14  and is joined at their horizontal centers  18 C by the middle brace  22 . The pair of cross braces  20  joins each of the middle bars  18  to the adjacent side bar  14 . The one pair of hinge plates  24 A connects the one end  14 A of each side bar  14  to one of the corner posts  12 A while the other pair of hinge plates  24 B connects the other end  14 B of each side bar  14  to the other of the corner posts  12 D. One pair of top and bottom hinge pins  24 C connect opposite ends of each hinge plate  24 A between the one end  14 A of each side bar  14  and one of the corner posts  12 A. Likewise, another pair of top and bottom hinge pins  24 D connect opposite ends of each hinge plate  24 B between the other end  14 B of each side bar  14  and one of the corner posts  12 D. 
     FIG. 4 is a side elevational view of the rack  10  taken along line  4 — 4  of FIG.  1 . In FIG. 4, opposite corner posts  12 A and  12 D are mounted in their foot plates  26 B. Each of the posts  12 A and  12 D has the end pin  12 E on top. The side bar  14  connects the opposite corner posts  12 A and  12 D at their bottom ends  12 B. Ends of the lower bars  16 B and the cross braces  20  are shown in phantom lines. The name plate  36  is mounted at the middle of the side bar  14 . Hinge plates  24 A and  24 B are shown in solid lines attached to the upper ends  12 F of the corner posts  12 A and  12 D, respectively, in their upright positions. Hinge pins  24 C and  24 D secure the hinge plates  24 A and  24 B, respectively, at opposite ends  14 A and  14 B of the side bar  14  with the upper ends  12 F of the corner posts  12 A and  12 D, respectively. 
     The collapsing of the pallet rack  10  may be best understood with reference to FIGS. 2 and 4. In FIG. 4, the rack  10  is shown with its corner posts  12 A and  12 D in their upright positions. In order to collapse the rack  10  into its folded position seen in phantom lines in FIG. 4, cotter pins  38  are pulled out in a direction of double-headed arrows B from aligned bore holes  12 H of FIG.  2  and the upper ends  12 F of the corner posts  12 A and  12 D are pulled slightly upwardly in a direction of arrows C in FIG. 2 to separate them at the seams  12 G from the bottom ends  12 B. 
     Returning to FIG. 4, the hinge plates  24 A and  24 B are then rotated 90° about the bottom hinge pins  24 C and  24 D, respectively, in a direction of arcuate arrows D. At the top hinge pins  24 C and  24 D, the hinge plates  24 A and  24 B each carry with them the upper ends  12 F of the corner posts  12 A and  12 D which likewise rotate 90° from their upright positions to horizontally collapsed positions shown in phantom lines. The cotter pins  38  are not lost during the folding steps because they are retained by wires  40  which are secured to sides of the bottom ends  12 B. 
     In FIG. 5, the rack  10  is seen in use in an end view. The upper ends  12 F of the corner posts  12 D are connected together by the upper end bar  16 A which carries on top at its horizontal center  16 C the cradle  32  with a deep inset and the holddown plate  34  fastened thereto. A central mandrel  42  of a large roll  44  of mechanically sensitive goods, such as paper or yarn, rests completely in the deep inset of the cradle  32 . Each heavy roll  44  is lifted at opposite ends of the mandrel  42  by either a crane or a forklift and is lowered into position in the inset of the cradle  32 . The holddown plate  34  is then fastened on top of the cradle  32  by pins  46  so that the mandrel  42  is secured in the inset of the cradle  32  in order to prevent it from jumping out in the event that the rack  10  suffers a strong external shock. Above the roll  44 , another rack  10  is partially visible with the foot plates  26 B of the bottom ends  12 B of the corner posts  12 D nestled over the top end pins  12 E. The lower end bar  16 B is seen in phantom lines and connects the adjacent bottom ends  12 B together. Brackets  28 A extend below the lower end bar  16 B to receive prongs of a forklift (not shown) and allow an operator to remove a rack  10  safely. At the bottom of each upper end  12 F of the corner posts  12 D, there are the blocks  12 J through which the bore holes  12 H are drilled. The hinge plates  24 B are also shown at the bottom of FIG. 5 with the top hinge pins  24 D which attach the hinge plates  24 B to the corner posts  12 D. The box  30  prevents the roll  44  from shifting in the rack  10 . 
     Clearly, numerous modifications and variations of the present invention are possible in light of the above teachings. Thus, it is to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.