Patent Publication Number: US-7216415-B2

Title: Pallet scuffing apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation of U.S. application Ser. No. 10/465,927, filed Jan. 15, 2004, now U.S. Pat. No. 6,938,321, which is a continuation of International Application No. PCT/US02/00032, filed Jan. 2, 2002, which, in turn, claims the benefit of U.S. provisional application Ser. No. 60/259,454 filed, Jan. 2, 2001. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to an apparatus for scuffing and for providing a slip-resistant surface to a plastic pallet which supports freight, goods, or other materials, to a process for preparing a slip resistant surface, and to plastic pallets thus prepared. 
   2. Background Art 
   Plastic pallets may have surfaces which tend to be slippery as a result of the material and molding process. Accordingly, measures may be taken to prevent loads from possibly sliding off the pallet, as well as to keep the stacked pallets from sliding off one another, and further, to keep the pallet from sliding off the forks of the fork lift or a lift track. Common anti-slip measures for pallets involve the use of anti-slip coatings or rubber inserts, such as pads or grommets, placed in strategic locations. Examples are shown in FIGS. 20–25 of U.S. Pat. No. 4,051,787. One drawback of these aforementioned anti-slip measures is that they require the installation of additional parts or materials to a finished pallet and thus required increased material and labor cost. Further, anti-slip coatings can wear away, and inserts can work loose and fall off during use, rendering them ineffective. 
   Another pallet scuffing technique is disclosed in U.S. Pat. No. 6,006,677, which discloses creating a multi-directional scuffing pattern by brushing the pallet surface with at least one cup-shaped wire brush. While this technique may be effective, a wire brush may not provide the desired level of slip resistance and scuffing desired in many industrial and heavy use applications. 
   Consequently, there is a need for a pallet scuffing apparatus and technique which provides anti-slip and anti-skid properties to plastic pallets. This apparatus and method should produce textures which do not easily wear away, work loose, or fall off during use. 
   SUMMARY OF THE INVENTION 
   An object according to the present invention is to provide a plastic pallet that has sufficient anti-slip and anti-skid features in the areas that provide support to the load, contact the fork of a forklift, as well as the areas which may contact the ground or other pallets in a stacked orientation. 
   Another object according to the present invention is to provide a plastic pallet wherein the anti-slip feature will not work loose or wear away, but instead is integral with the pallet. 
   In keeping with the above goals and objects according to the present invention, provided is an improved plastic pallet having a load bearing surface with an improved slip resistant, scuffed texture formed integrally therein. The pallet may also include a bottom surface and a fork contacting region which also include a slip resistant, scuffed texture. In one embodiment, the plastic pallet includes an upper deck and a lower deck, the upper deck having a top surface and the lower deck having a bottom surface. Thus, the top surface defines the load contacting surface, and the bottom surface defines the lower contact surface. The upper deck may also include a bottom surface which defines the fork contacting region and which also includes the slip resistant, scuffed texture. The scuffed texture may be formed on the pallet in a unilateral direction or in a multi-directional pattern. A preferred method of defining the scuffed texture on the pallet is by applying a surface preparation tool having multiple cutters. 
   The objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings wherein like reference numerals correspond to like components. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of the apparatus according to the present invention as applied to a pallet surface; 
       FIG. 2  is a perspective view of the cutter bundles and spindles of the apparatus according to the present invention; 
       FIG. 3  is a perspective view of a cutting disk from the cutter bundles according to the present invention; 
       FIGS. 4 ,  5 , and  6  are views of a plastic pallet sections to which the apparatus disclosed herein has been applied to a surface thereof. 
       FIG. 7  is a side view of an alternative apparatus according to the present invention as applied to a pallet surface; and 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
   A pallet  10  is provided according to the present invention. Pallet  10  includes an upper surface  12  and a lower surface  14 . In one embodiment, the pallet includes an upper deck  16  which includes upper surface  12 , and a lower deck  18  which includes bottom surface  14 . Upper surface  12  is typically the load bearing and load contacting surface, while bottom surface  14  is the pallet support surface, and generally contacts the ground, floor or other pallets when positioned in a stacked orientation. 
   Pallet  10  is preferably injection molded and formed of from a thermoplastic material, such as high density polyethylene or polypropylene. The material used to form pallet  10  may have a rather slippery surface just after molding and when the pallet is new. This slippery surface is undesirable in certain areas, such as the top surface  12  of upper deck  16 ; the bottom surface  14  of lower deck  18 ; and also the lower surface  20  of upper deck  16 , and the areas between the columns or supports  22 , these being the areas which are adapted to rest on the forks of a forklift when in use. 
   In accordance with the teachings of the present invention, in order to achieve the desired anti-slip and scuffing properties, a pallet scuffing apparatus  30  is applied to the desired surfaces ( 12 ,  14 ,  20 ) of pallet  10 . Apparatus  30  includes at least one and preferably a plurality of cutter bundles  32 , each of which is fixedly mounted to a spindle  34  to provide rotational movement to the cutter bundles  32  (See  FIGS. 6 ,  7  and  8 ). While upper surface  12  and lower surface  14  may be treated to this scuffing technique at any time, it is contemplated that the fork contacting region  20  is scuffed before the upper and lower decks  16 ,  18  are joined together. 
   The cutter bundles  32  are of the type manufactured by Aurand Manufacturing and Equipment Company, Inc. located in Cincinnati, Ohio, and sold as part of cutting tools bearing Model Nos. M5-1/M5-1E, and M5-2/M5-2E. The cutter bundles  32  themselves may be of the type bearing Model No. 90M. Such cutter bundles  32  in association with the cutting tools are used to remove paint, rust, and scale from wrought iron, large pipes, tanks and valves, beams and girders, and for scoring concrete. Accordingly, while such cutter bundles  32  have been used to remove coatings from typically metallic surfaces, the teachings according to the present invention apply the cutter bundles  32  to various surfaces  12 ,  14 ,  20  of a plastic pallet  10  in order to abrade the surfaces and provide an improved anti-skid and anti-slip scuffing surface. The cutter bundles  32  are typically formed of high quality steel, and under some circumstances, it may be necessary to apply a cooling liquid, such as water, to the cutter bundles during operation. Particularly, the cutter bundles  32  include a plurality of bundled serrated disks  26  (see a type of individual disk  26  in  FIG. 3 ) fixedly mounted adjacent to each other. 
     FIGS. 4 and 5  illustrate a corner portion  50  of a plastic pallet  10  to which the apparatus  30  having cutter bundles  32  according to the present invention have been applied. As illustrated in  FIGS. 1 and 4 , the cutter bundles  32  perform a shearing action against the pallet surface, thereby causing the teeth  27  to scrape or gouge the pallet surface, shaving the appropriate surface of the pallet  10  in order to lift up various portions of plastic material. This shaving creates a plurality of relatively small plastic peels  52 , as shown in  FIG. 5  much of which remain attached to the pallet  10 , resembling a napped surface. This provides a desired scuffed, anti-slip surface not provided by those techniques and devices of the prior art. Note that some of the plastic peels may become separated from the pallet during the scuffing process, thereby defining an improved roughened plastic surface. 
     FIG. 6  illustrates an additional alternative and enlarged view of the corner portion  50  of plastic pallet  10  to which the apparatus  30  having cutter bundles  32  according to the present invention have been applied. 
   As shown in  FIGS. 1 and 2 , the cutter bundles  32  may be mounted to an automated apparatus fixture  30  for treating pallet surfaces, for example, on an automated line after molding and optionally cooling of the pallet. In this embodiment, the apparatus  30  includes a plurality of cutter shafts  34  oriented generally parallel to each other and spaced apart. The cutter bundles  30  are fixedly mounted to the cutter shafts  34 . The shafts  34  rotate at a speed appropriate to the desired application. The shafts  34  may be driven with a single power source, and may also include a gearbox to modify the speed of rotation. As shown in the simplified schematic illustration of  FIG. 1 , as the pallet  10  moves along the line as designated by arrow  38 , a first spindle  34  rotates cutter bundles  32  clockwise (in the direction of arrow  40 ), while a second spindle  34 ′ rotates cutter bundles  32 ′ counter-clockwise (in the direction of arrow  42 ), such that the teeth  27  of the serrated disks  26  cut into the pallet surfaces in order to define the scuffed surface. Apparatus  30  may also include a depth shoe to limit the depth into the pallet surface that cutter bundles  32  shave, which by example and not limitation may be a cutting depth of 1.0 mm. As shown in  FIG. 2 , it is contemplated that the cutter bundles  32  of one shaft  34  are oriented in an offset manner from the cutter bundles  32 ′ of the other shaft  34 ′, such that adjacent sections of the pallet have a scuffing texture in opposite directions. 
   It is also contemplated that cutter bundles  32  may be applied to the pallet surfaces to create multi-directional surface scuffing. As shown in the simplified schematic illustration of  FIG. 7 , apparatus  30 ′ includes cutter bundles  32  and  32 ″ are oriented in a perpendicular relation to each other, such that cutter bundle  32  is applied to surface  12 , and then cutter bundle  32 ″ takes a subsequent pass on surface  12 , thereby shearing the surface in a plurality of directions and improving the slip resistance of the surface in a plurality of directions. Of course, while the cutter bundles  32  are shown as oriented in a perpendicular manner, they may be oriented in any number of orientations to define the multi-directional slip resistance to the pallet surface. 
   The cutter bundles  32  may be moved past the pallet surface, or preferably, the cutter bundles are fixed in position and relative movement between the cutter bundles and the pallet  10  may be accomplished by a carriage, i.e. a moving belt or series of links on which the pallets are placed or mounted. Any conventional means of producing relative movement of the cutter bundles and the pallet may be used. 
   While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.