Patent Publication Number: US-6705236-B1

Title: Indexed pallet

Description:
This application is a 371 of PCT/US 00/04279 filed Feb. 18, 2000 which is a continuation of U.S. Ser. No. 09/253624 filed Feb. 19, 1999, U.S. Pat. No. 6,209,464. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a pallet and in particular, to an indexed pallet and alignment system for aiding in positioning the pallet for loading and unloading. 
     2. Prior Art 
     Pallets for supporting various types of articles are well known. Pallets are made of many materials including wood, metal, fiberglass or molded plastic, depending on the intended use and environments in which the pallets are used. Pallets generally provide a support for many different types of articles and are adapted for use with many types of loading equipment, including attachment to cranes or lifting from below by forklifts or manual pallet jacks. 
     Pallets are often constructed with a planar supporting upper surface and feet, runners or other supports extending downward from below the planar support portion. In this manner, articles are raised off of the ground to prevent moisture, dirt and other debris from coming into contact with the supported articles. When not in use, the pallets are typically stored in a stacked configuration. The stacks may become very high and the amount of space required for storing the pallets may be quite expansive. 
     Pallets often require precise positioning of the articles for loading and unloading. Often channels are formed across the supporting surface so that tines or extended fingers may fit under the supported articles into the channels for aiding with alignment. However, this method may introduce imprecision due to variances and tolerances in the channels into which the tines or fingers extend in aligning and positioning of the articles for loading and unloading. This problem can be compounded if measurements are taken from different positions, such as opposite ends of the pallet. 
     It can be seen then that a pallet is needed that is capable of supporting heavy loads and provides maximum support area that does not damage articles being supported and are stackable when not in use. In addition, such pallets should provide for alignment of the pallets for loading and unloading in a precise manner without detracting from the utility of the pallet. Such an alignment system should prevent misalignment due to differences in tolerances from one end to the other of the pallet. 
     SUMMARY 
     The present invention is directed to a stackable pallet and in particular, to a pallet that includes an alignment portion to aid in precisely positioning the pallet. 
     The pallet may be made of a molded plastic or other similar material that is light weight and provides sufficient strength to accommodate the anticipated loads. The pallet includes a deck with a substantially planar upper surface and support portion extending downward from an underside of the deck. The upper surface may include channels formed therein and extending across the width of the deck. Ribs extending on the underside of the deck preferably run crosswise to the channels so that the deck has improved strength and rigidity. The underside of the deck may also include indentations for receiving the support portions of adjacent pallets stacked in a flip-flop configuration so that the supports of one pallet inserted into the indentations of an adjacent inverted nested pallet. In this manner, the pallets may be stacked and nested, alternately inverted pattern requiring less overall height and less space for the stored pallets. The bottom of the support portions are configured to also extend into recesses formed in the upper surface of the deck so that the decks nest slightly in a normal stacked configuration. This retards lateral sliding of the decks and provides alignment so that the stack is less likely to tip. 
     In addition, the pallets of the present invention include an alignment notch formed along the center line of one of the lengthwise edges of the pallet. The alignment notch has angling sides which align with and receive a complementary alignment member from a device from the structure with which the pallet is being aligned. The angling sides provide for a degree of self correcting alignment. With the notch along the center line, the tolerances and variations are decreased as aligning is always taken from the center point rather than one of the ends where variances and tolerances may compound. 
    
    
     These features of novelty and various other advantages which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings which form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring now to the drawings, wherein like reference numerals and letters indicate corresponding structure throughout the several views: 
     FIG. 1 shows a perspective view of a first embodiment of a pallet according to the principles of the present invention; 
     FIG. 2 is a top plan view of the pallet shown in FIG. 1; 
     FIG. 3 is a side elevational view of the pallet shown in FIG. 1; 
     FIG. 4 is an end elevational view of the pallet shown in FIG. 1; 
     FIG. 5 is a bottom plan view of the pallet shown in FIG. 1; 
     FIG. 6 is a side elevational view of pallets shown in FIG. 1 in a stacked, nested configuration; 
     FIG. 7 is a side elevational view of pallets shown in FIG. 1 in an alternately inverted stacking pattern; 
     FIG. 8 is a perspective view of the pallet shown in FIG. 1 with an indexing element of an alignment device; 
     FIG. 9 shows a top plan view of the pallet shown in FIG. 1 with the stackable pallet and indexing element engaged; 
     FIG. 10 shows an end detail view of the ends of the channels of the stackable pallet shown in FIG. 1; 
     FIG. 11 shows a side elevational view of a second embodiment of a pallet according to the principles of the present invention; 
     FIG. 12 shows a top plan view of the embodiment shown in FIG. 11; 
     FIG. 13 shows a bottom plan view of the embodiment shown in FIG. 11; 
     FIG. 14 shows a bottom detail view of an alignment portion for the pallet shown in FIG. 11; and 
     FIG. 15 shows a sectional view taken along line  15 — 15  of FIG.  14 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, there is shown a pallet, generally designated  10 . The pallet includes a deck portion  12  having a substantially planar upper surface and may include ribs  15  and channels  16  extending across the upper surface. The channels  16  may receive supports or lifting devices for the load. The ends of the ribs  15  are tapered to aid insertion. The pallet  10  includes support members  14  extending downward from an underside of the deck  12 . The support portions  14  are spaced apart from one another to provide a wide stable base for the pallet and adapted to receive forklift tines and manual pallet jacks. The supports  14  at the corner include vertical sides that are substantially flush with the edges of the deck  12 , as shown in FIGS. 3 and 4. 
     As also shown in FIG. 2, the upper surface of the deck  12  includes recesses  18  formed for nesting of the pallets  10  when stacked. The recesses  18  define center portions  20  extending to the upper surface of the deck  12  that are configured for nesting and aligning with bottom depressions  24  and lower surfaces formed in the bottom of the support portions  14 , shown in FIG.  5 . The lower surfaces  22  of the support portions  14  have a profile complementary to the recesses  18  so that the pallets  10  nest when stacked to prevent lateral movement between stacked pallets  10 . Referring again to FIG. 5, the underside of the pallet  10  includes bottom support ribs  26  extending across the length of the pallet. The ribs  26  extend perpendicular to the ribs  15  and channels  16  on the top of the deck  12  for improved support and rigidity. The nesting recesses  18  also provide compatibility with the channels  16  and preferably extend to a depth no greater than the channels  16 . 
     The underside of the deck  12  includes cavities  28  formed therein that are spaced and configured for receiving lower surfaces  22  of the support portions  14 . In this manner, pairs of the pallets  10  may be stacked in a flip-flop configuration with greater nesting occurring. The pairs of pallets  10  are stacked slightly offset to one another so that the support portions  14  of one pallet  10  align with and extend into the bottom cavities  28  of an inverted adjacent pallet  10 . This configuration prevents lateral sliding between pairs of complementary pallets  10 , requiring less space for pallet storage and shipping. 
     Referring again to FIG. 1, the pallet  10  includes an alignment section  40  shown as a notch along opposed edges of the planar deck  12 . The notches  40  are substantially “V” shaped and may include an enlarged tip portion  42 . The alignment section is preferably positioned along the center line of the long edge of the deck  12 . In this manner, more precise alignment is achieved as differences due to tolerances are measured from the center line rather than accumulating over the entire length of the pallet  10 . Mistakes due to alignment from different ones of the two ends are also eliminated. The planar deck  12  has an alignment section  40  along both of the longer edges of the deck  12  in a preferred embodiment so that either of the opposed edges may be used for alignment. The alignment section  40  is configured for mating with an alignment member  102  of a stationary device  100  with which the pallet  10  is being aligned, as shown in FIGS. 6 and 7. The alignment member  102  has a substantially triangular end portion having angling surfaces  104 . The pallet  10  is aligned by moving the deck so that the alignment section  40  engages the alignment member  102 . As the angled sides of the notch portion  40  and the angling surfaces  104  engage one another, they provide for self-alignment as the pallet  10  is moved closer to the stationary device  100 , as shown in FIG.  7 . The system provides self-alignment and assures repeated identical positioning among all pallets  10  as they are aligned with the device  100 . This allows precise placement of the load for handling equipment. 
     Referring now to FIG. 10, the channels  16  further from the alignment section  40  are wider than the channels closer to the alignment section. Channels  16 A have a first width, channels  16 B have a second width greater than the first width, and channels  16 C have a third width greater the first or second width. In some instances, elongated tines, commonly known as swords, are in a fixed position when inserted into the channels  16  of the pallet  10 . Gradually widening channels  16 A,  16 B and  16 C allow for variations due to compounded tolerances in the channels furthest from the center of the pallet  10 . The swords may be easily inserted as width of the channels  16  increases in a manner somewhat corresponding to increased variations from compounded tolerances. Moreover, since the alignment is based from the center of the pallet  10 , the variations can only compound over half the length of the pallet  10 , thereby decreasing the maximum variations as compared to alignment from one or the other of the ends. In a preferred embodiment, the centerlines of the channels  16 A,  16 B and  16 C remain evenly spaced apart even though the channel width increases, as the swords are evenly spaced apart. 
     The alignment system provides a self-centering mechanism and provides for precise alignment while minimizing differences in tolerances or alignment from different ends of the pallet  10 . The pallet  10  may be a light weight molded monolithic element that includes alignment features  40 . 
     Referring now to FIG. 11, there is shown a second embodiment of a pallet, generally designated  210 . The pallet  210  is similar to the pallet  10  shown in FIG. 1, however, the second embodiment pallet  210  includes a different notch  240  formed for alignment of the pallet. Opposed notch portions  240  are formed below the planar deck  212  proximate a centerline of the pallet  210 , as explained hereinafter, and do not extend up to the deck  212 . With this configuration, the planar deck  212  does not include a notched portion and is extended to the edge of the pallet, so that a continuous straight edge is formed. Without a center notch formed in each side, increased support area is provided. The pallet  210  includes a number of supporting members  214  extending downward from the underside of the deck  212 . Ribs  215  extend across the upper surface of the planar deck  212 , as shown in FIG.  13 . Channels  216  are formed between the ribs  215  across the upper surface of the planar deck  212 , as shown in FIG. 12, and may be spaced similarly to channels  16 . The planar deck  212  also includes banding holes  218  extending through the planar deck  212  in the channels  216  and configured to receive straps for securing loads on the pallets  210 . The banding holes  218  may also be combined with the recesses  18  for improved stacking and loading. 
     Referring again to FIG. 13, the underside of the deck  212  includes support member surfaces  222  for each support member  214  forming a bottom center depression  224 . Support ribs  226  on the underside of the deck  212  extend transversely to the deck ribs  215  and channels  216  for improved support and stability. 
     At the side center support member  214 , the notch portions  240  are formed, as shown in FIGS. 14 and 15. Converging angled sides  244  form a nut portion and a rounded tip which may be configured from receiving a complementary alignment member, such as a roller. The sides  244  also angle inward to provide better guidance and alignment. The notch portion  240  stops below the planar deck portion  212  to provide greater support area for the deck  212 . The notched portion  240  is also configured with a narrowed section  246  between an upper section notch for receiving an alignment member of a stationary device and a lower section for guiding a complementary alignment device. As with the first embodiment notch  40 , the notched portion  240  provides alignment of the pallet from its center relative to another surface, but also provides an upper deck providing support extending to the edge along its entire length. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.