Abstract:
A half pallet that is capable of easy assembly, functionally adequate for some situations and capable of easy disassembly in an environmentally acceptable manner. In one form of the pallet, a half pallet is provided that is made of all wood. In one embodiment, the half pallet may be comprised of a plurality of stringers with bores, a plurality of deck boards with openings, and a plurality of wooden dowels disposed in the bores and openings to connect the stringers and deck boards.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to pallets, and more particularly to a half pallet having deck boards connected to stringers with wooden dowels. 
       BACKGROUND OF THE INVENTION 
       [0002]    Pallets of various types are known in the art. Pallets of the stringer design are constructed of wood and include parallel stringers to which transverse deck boards are then nailed or otherwise secured with metal fastener devices to form the pallet. Pallets of the block design have wooden blocks at the corner and central locations to support the load. Pallets need to have sufficient strength to withstand the weight of objects loaded thereon and other impact forces to which the pallets are subjected when objects are loaded onto them and when the pallets are moved, as by a fork-lift truck or the like. 
         [0003]    In many pallets, pallets are most often damaged at their lead boards. As a fork lift or other mechanism is brought to engage a pallet, the tines of the fork lift will often impact the lead board of the pallet with significant force. This shearing force may disengage the lead board or otherwise damage it, yielding a worn or damaged pallet that may not work as well and may be dangerous to users and merchandise. 
         [0004]    Also, as pallets are used, they can become worn and weakened, causing some of the stringers or deck boards to break or become at least partially detached, rendering the pallet inoperable or in a dangerous condition. The use of nails or other metal fastener devices can also render pallets dangerous. Many times, the damage to a pallet occurs where the metal nail goes into the wood. The use of metal fasteners can cause splitting in the stringers or deck boards. Further faults include product damage or personal injury caused by exposed fasteners and inadequate joint stiffeners. 
         [0005]    In an effort to save money and resources, the undamaged portions of worn or damaged pallets are often salvaged and reused in making recycled pallets, used as fuel or sawdust, or put to other uses. Those in the art have employed many methods in their attempts to salvage worn-out pallets by stripping or otherwise disassembling the stringers and deck boards from each other. However, many of these methods require costly machinery or a great deal of time and effort and put workers at significant safety risk. Nails and other metallic fasteners are often a great hindrance in efforts to disassemble pallets. The presence of, for example, nails prevents the use of standard saws or similar devices, which do not effectively cut through nails. Devices that are able to disassemble worn-out pallets that include nails face other disadvantages. First, they are often large, unwieldy and expensive. Second, often times the nails remain in the stringers or deck boards after disassembly. In order to reuse the boards in optimal condition, the nails need be removed, requiring additional time with attendant increased cost and expense. 
         [0006]    It is also attractive to retail stores to use half pallets to allow the pallets to be used within the stores in the aisles to distribute product directly from the pallets to the shelves. This procedure increase efficiency and reduces the time spent in distribution. However, half pallets present problems in maintenance of the proper sizing of the notches or openings for the fork tines of forklifts or hand jacks, while simultaneously maintaining the strength and durability of the overall pallet. Because a nail or screw cannot be driven too close to the edge of a stringer without splitting the stringer, there is a minimum thickness of the stringer that can be used. If the stringer is thicker than this minimum allowance, the opening for the fork tines is not wide enough and thus the pallet becomes unusable. 
         [0007]    A half pallet is generally 24 inches by 40 inches although it can be smaller as larger. The openings, or notches, allowing for entry of the fork times must be at least 21 inches from end to end. If the stringers or blocks are too thick or otherwise are positioned to reduce the notch to less than 21 inches, then the utility of the half pallet is greatly reduced. 
         [0008]    It is therefore a primary benefit of the subject invention to have a half pallet that is all or substantially all wood, and provides for openings of at least 21 inches wide. 
         [0009]    It is a further benefit of the subject invention to increase strength while reducing weight with an all wood or substantially all wood half pallets through the use of a dowel in a bore parallel with the grain of the wood stringer or block. 
         [0010]    Another benefit of the present invention is to provide a half pallet that can be easily assembled through the use of wooden dowels that facilitate attachment of transverse deck boards to parallel stringers or blocks in a quick and efficient manner. 
         [0011]    Another benefit of the present invention is to provide a half pallet that works properly. The dowels provide for a connection that is sufficiently strong to resist standard shear and other forces. 
         [0012]    Another benefit of the present invention is that the edge and end distance of the vertical dowel fasteners in the pallet assembly can be different than typical steel fasteners which require more edge or end distances. 
         [0013]    Another benefit of the present invention is that the intersection of all wood to wood joints can be glued with either a chemical or mechanical type adhesive. 
         [0014]    Another benefit of the present invention is to provide a half pallet that can be more easily disassembled. In the preferred embodiment the dowels are made of wood; therefore, the pallet can be more readily stripped or broken down using standard wood-cutting saws. This allows for an increased number of customers for used or worn pallets, because those customers have no need for specialty equipment to grind up nails. 
       SUMMARY OF THE INVENTION 
       [0015]    In carrying out one embodiment of the invention, a half pallet is made predominately of wood, generally Southern yellow pine, oak or a combination thereof. The half pallet of the subject invention comprises a plurality of wood deck boards, stringers, and blocks. Each wooden stringer comprises four elongated longitudinal surfaces and two end surfaces. A selected longitudinal surface is designated as a mounting surface and has a plurality of bores formed therein so that the longitudinal axes of the bores are generally normal to the mounting surface. The size and shape of the bores can range from a depth completely through the deck boards and stringers to a smaller depth sufficient to receive a portion of a dowel. 
         [0016]    The deck boards can be connected to the stringers by a plurality of wooden dowels. The dowels may be completely cylindrical or it may have a first and second portion, comprising at least two contiguous dowel sections having different cross-sectional size, which can mate with a corresponding configuration of the bore, thereby connecting the stringer to the deck board. Adhesive is used to augment that connection. The second end of the deck board can be similarly connected to a second stringer so that the deck board is transverse to the wooden stringers. A pallet can be formed by so connecting a plurality of deck boards to the stringers. In lieu of some of the stringers, blocks can be utilized for a block pallet. 
         [0017]    The substantially all wood half pallet of the subject invention has a plurality of wooden pallet upper and lower stringers, deck boards and blocks positioned to form a half pallet, the deck boards being parallel to one another, the upper stringers being spaced, and parallel to one another in a horizontal plane, and transverse to and adjacent the deck boards on an upper surface, and adjacent a block on an opposite surface for forming a 24″×40″ rectangular shape. Each block is positioned with its grain substantially perpendicular to the horizontal plane of the stringers, with the edges of the deck boards and the upper and lower stringers being in the same vertical plane. The deck boards have a mounting surface and a top surface; the half pallet has through openings on each side to allow for the insertion of pallet forks from any side. The deck boards have pilot holes extending substantially perpendicular to the mounting surface through the deck boards and into adjacent stringers and blocks, the pilot hole being completely through the deck board, and spaced from zero to about 3/16 inch to ½ inch away from the edge of the stringers, blocks and the deck boards. Additionally, the dowels may be positioned with no space between them. i.e., adjacent one another and touching. Adhesive is disposed on the mounting surfaces and in the pilot holes and a plurality of wooden dowels disposed in the pilot holes such that the top surface of the pallet deck boards and the top surface of the dowels are substantially co-planar, wherein the dowels connect the deck boards, stringers and blocks through a cinching action on at least the deck boards. 
         [0018]    The pallet of the subject invention also may include a plurality of deck boards, each deck board including a longitudinal mounting surface having a plurality of vertical bores formed therethrough, a plurality of deck boards, upper and lower stringers, and blocks, each having a plurality of substantially vertical openings, each of the vertical openings corresponding to a vertical bore. Each of the vertical openings and vertical bores are from 3/16 to ½ inch from an edge of a stringer, block and deck board. The deck boards are spaced and parallel. The stringers are spaced and transverse to the deck boards, with the deck boards vertically adjacent the upper stringers. The blocks are between the upper and lower stringers, and have a vertical grain parallel with the vertical bores. A plurality of wooden dowels are inserted through the vertical bores of the deck boards through to the plurality of respective vertical openings such that the deck boards stringers and blocks are connected together in a predetermined orientation to form a half pallet, whereby the half pallet has openings sufficiently large to permit entry of fork lift tines on each of the four sides of the half pallet. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The drawings may not be to scale. The invention may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which: 
           [0020]      FIG. 1  is a perspective view of one embodiment of a half block pallet that may be used in the pallet of the subject invention; 
           [0021]      FIG. 2  is a magnified view of a corner region of the block pallet of  FIG. 1 ; 
           [0022]      FIG. 3  is a cross-section taken along the lines  3 - 3  of  FIG. 1 ; 
           [0023]      FIG. 4  is a cross-section taken along the lines  4 - 4  of  FIG. 1  of a stringer secured to a block by a dowel; 
           [0024]      FIG. 5  is a side plan view of a dowel that may be used in the subject invention. 
           [0025]      FIG. 6  is a perspective view of an alternate embodiment of the subject invention. 
           [0026]      FIG. 7  is a bottom view of the embodiment of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    While the present invention is susceptible of embodiments of various forms, there is shown in the drawings, and will hereinafter be described some exemplary and non-limiting embodiments, with the understanding that the present disclosure is to be considered an exemplification of the invention. It is not intended to limit the invention to the specific embodiments listed. 
         [0028]    In general terms, one embodiment of the invention comprises the combination of wooden dowels and adhesive to connect stringers, deck boards and blocks to form a half pallet. 
         [0029]    Referring to  FIG. 1 , deck boards  10  and stringers  14 ,  15  can be seen. The deck board  10  has a first end  11  and a second end  12 . The deck board  10  may comprise about a ⅝″×4″×40″ board. The stringers  14 ,  15  may comprise about a ⅝″×4″×24″ board. Between the bottom stringers  14  and upper stringers  15  are six 4″×4″×⅝″ boards on blocks  16  on the outside of the long or 40 inch side and with three 4″×4 ″×4″ blocks  17  in the inside of the center of the short or 24″ side, constituting a type of block pallet. Because this pallet is to be a half pallet, the number of stringers, blocks and deck boards is reduced accordingly so that the pallet measures 40″ by 24″. Other sizes may be utilized, depending on a customer&#39;s requirements. The upper stringers  15  and the lower stringers  14  are each secured to a block  16  or  17  by a dowel or dowels  50 . Blocks  16  are located at the corners and in the middle of the long sides. Blocks  17  are in the middle of the short side as well as in the overall middle of the half pallet. Blocks  16  and  17  are positioned between upper stringer  15  and lower stringers  14  so that the sides of blocks  16  and  17  are flush or even with the sides of the deck boards, upper stringer  15  and lower stringer  14 , i.e., the edges of each are in the same plane. 
         [0030]    Each stringer  14 ,  15  has a plurality of predrilled bores  31  defined therein. The terms bore and opening are herein used synonymously. 
         [0031]    Referring to  FIG. 5 , one embodiment of a wooden dowel  50  can be seen. The dowel  50  can comprise a first portion  52  and a second portion  54 . The dowel may have a plurality of dowel sections, a first section  56 , middle sections  58 ,  60 , and last section  62 . While in a preferred embodiment, the dowel  50  has two middle sections  58 ,  60 ; other embodiments may have no middle section, one middle section, or three or more middle sections. The first and last sections  56 ,  62  may have side walls  64 ,  66  and end walls  68 ,  70 , respectively. Each of the middle sections  58 ,  60  may have side walls  72 ,  74  and step walls  76 ,  78 , respectively. In a preferred embodiment, each of the sections  56 ,  58 ,  60 ,  62  are contiguous to another section  56 ,  58 ,  60 ,  62 . The sidewalls  64 ,  66 ,  72 ,  74  define a cross-sectional size for their respective sections  56 ,  58 ,  60 ,  62 . In a preferred embodiment, the cross-sectional size of the sidewalls  64 ,  66 ,  72 ,  74  decreases as one progress from the first section  56  to the last section  62  in a number of steps. In another embodiment, the cross-sectional size of the sidewalls is greatest in a middle section (not shown). The cross-sectional size of the sidewalls  64 ,  66 ,  72 ,  74  may be any suitable size. The length of each individual dowel section  56 ,  58 ,  60 ,  62  may vary considerably. In one embodiment, the dowel section  56 ,  58 ,  60 ,  62  with the smallest cross-sectional size is as long or longer than the length of any of the other dowel sections. The dowel  50  may have some sections, e.g.,  58 ,  60  or all sections  56 ,  58 ,  60 ,  62  that have grooves  80 . The dowel  50  may have other configurations, such as the dowel shown and described in U.S. Pat. No. 6,267,527, which is hereby incorporated by reference. While the above described dowel is preferred, it is anticipated that a dowel of solely cylindrical dimensions may also be used. 
         [0032]    As shown in more detail in  FIGS. 3 and 4 , the bores for the dowels are drilled within zero, i.e., on the edge, to ½ inch, preferably 3/16 to ½ inch from the edge of the stringer and block, and more preferably 5/16 inch from the edge. Further, the bore can be drilled adjacent and touching one another so that the dowels can be positioned where needed, and as close to one another as necessary, without splitting the wood, as happens if nails are driven in too close together. Because the bore is drilled, this can be accomplished without splitting the wood, as would happen if nails were to be used. By this feature the size and weight of the blocks, the stringers, and the deck boards can be reduced without sacrificing strength, and the blocks can be made flush with the edges of the stringers, thus making the openings for the fork tines larger (over 21 inches) and a bigger target to lessen the damage done by the fork tines when missing the opening. In addition, at least blocks  16  and possibly blocks  17  are positioned so that the grain of the blocks is vertical. Blocks  17  may have a horizontal grain. In this manner, when glue is applied to the bore, the glue will migrate further into the block along the grain lines, for a more secure holding action. Further each of the blocks will be strengthened by the vertical grain. With a vertical grain, the blocks will also be later able to withstand a hit from the fork tines, as the vertical grain will be less likely to split upon impact. 
         [0033]    As shown in  FIG. 4 , the dowel  50  connects the stringers  14 ,  15  to the deck board  10  and the block  16 . The opening  31  of the deck board  10  is configured to receive the shank  52  of the dowel  50 . The opening  31  is preferably sized so that it is slightly smaller than the dowel shank portion  52  that it is configured to receive. The dowel  50  then fits snugly into the opening  31 . Preferably, the dowel  50  and the opening  31  form a friction fit. This receipt of the dowel shank  52  in a cinching fashion is achieved by machining the bore of the stringers  14 ,  15  to a smaller cross section area in the stringer or second wood piece. Thus, the bore cinches or grabs the dowel portion  52 . While the bore is receiving the dowel in a cinching fashion, the bore or opening  31  in the first piece of wood or deck board is machined so that the opening  13  in deck board  10  is the same size or larger than dowel  50  cross sectional area. This means that the dowel  50  fits into the bore of the stringers  14 ,  15  in a cinching and grabbing fashion caused by the compression of the dowel surface by the surrounding wood on the surface of the pilot hole for a tight grip caused by the ratio of the dowel cross sectional area to the pilot hole cross sectional area being greater than one. The forgoing allows for the dowel to act like a nail in pulling the first piece of wood tightly to the second piece of wood. The dowel  50  can be substantially or fully inserted into the opening  13  and bore of the stringers  14 ,  15  through the use of a suitable pounding device (not shown), such as a hammer or mallet, or through manual strength. The dowel  50  may fit snugly into the selected opening  13  and bore. Preferably, the dowel  50  and the opening  13  and bore  31  forms a friction fit. In the joinder of the stringers, deck boards and blocks, adhesive is used. The application of adhesive material (not shown) to the stringers  14 ,  15  and deck boards  10  is such that some of the adhesive material is disposed in the bores and openings  13 . The adhesive material which may be a mechanical or chemical adhesive, may be applied to the surfaces of the stringers  14 ,  15 , deck boards  10  or side walls of the dowels  50  to strengthen or augment the connection. The adhesive material is preferably PVA, but can be any material that would adequately connect the parts of the pallet together, such as, e.g., elastomers, hot melts, urethane, epoxy, PRF, or urethane/isocyanate. Preferably, during the construction of a pallet, the adhesive is applied to the stringers  14 ,  15 , and deck boards  10  such that some of the adhesive is disposed in the bores of the stringers and openings  13  prior to the insertion of the dowels  50 . The adhesive material may also be applied to the side walls of the dowel  50 . In a preferred embodiment, the adhesive applied to the dowel  50  is thinned to allow for more ready insertion and connection. As the dowel is inserted into the bore or opening  13 , the adhesive material may be at partly scraped from the side walls to accumulate on the end wall and step walls. When a standard dowel is used, then the opening of both the stringer and the block is sized to be slightly smaller than the dowel in diameter so that the cinching action takes place. 
         [0034]    In a preferred embodiment, the half pallet described herein consists essentially of wood and adhesive. In the most preferred embodiment, the pallet consists of wood and adhesive. The use of a wooden dowel  50  with wooden stringers  14 ,  15 , and deck boards  10  and blocks  16  and  17 , along with adhesive, can, through construction, create a half pallet that is lightweight and yet exceeds industry requirements for static strength, stiffness, and resistance to rough handling. 
         [0035]    Further, the pallet described herein can be substantially lighter and stronger than standard half pallets that employ nails or other metal fasteners. First, the use of wooden dowels inserted into bores or openings instead of nails creates less weight. The weight of the dowel  50  being inserted is offset by the amount of wood drilled out of the deck boards  10  and stringers  30 . With the use of nails, there is no offset. With the use of a large number of nails in typical pallets (sometimes over one hundred for a used pallet), this weight difference can become substantial. Second, the pallet described herein can be made with kiln dried wood, which is lighter than wet or green wood. Typical pallets are made of wet or green wood because hammering in nails in dry wood can cause damage to the wood, such as checking, and result in a damaged or weakened pallet. Through the use of the dowel  50 , the pallet described herein can be constructed of wood that is kiln dried. Preferably, the wood is less than 15% moisture and more preferably between 9 and 12% moisture. The pallet described herein can be substantially lighter than typical pallets, about 28 lbs, where other commercial half-pallets are 38 lbs or more. Being lighter, the half pallets of the subject invention are less likely to cause injury to workers during transport, and also yield substantial savings in fuel economy during transport. 
         [0036]    In a second embodiment, the half pallet of the subject invention has an additional 2 or 3 stringers  18  added as a bottom support (see  FIGS. 6 and 7 ). These bottom stringers permit the half pallet to be racked, i.e., stored on top of another loaded pallet. It is not necessary to add more dowels or change any other feature of the pallet. 
         [0037]    The present invention is not limited to the particular details of the method depicted and other modifications and applications are contemplated. Certain other changes may be made in the above-described method without departing from the true spirit and scope of the invention herein involved. For example, the present method may be utilized with other styles of pallets, which have different formations of stringers, panel boards, or like members. It is intended, therefore, that the subject matter in the above depiction shall be interpreted as illustrative and not in a limiting sense.