EP1551720A2

EP1551720A2 - Reinforced paperboard pallet and runner and associated manufacturing system and method

Info

Publication number: EP1551720A2
Application number: EP02748059A
Authority: EP
Inventors: John R. Perazzo
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-02
Filing date: 2002-07-02
Publication date: 2005-07-13
Also published as: CA2489483A1; EP1551720A4; AU2002318184A1; MXPA05000002A

Abstract

A pallet (10) includes a number of runners (12) which may be sandwiched between upper and lower deck sheets (16, 18) of corrugated paperboard. Each runner (12) is comprised of multiple layers of corrugated paperboard (36) with the flutes (38) of the corrugations oriented vertically to provide compression strength to the runners (12) and the associated pallet (10). Each runner (12) also may include at least one reinforcing insert (40) most preferably of hardboard to provide beam strength to the runner (12) and a band (35) to avoid failure without a prior indication. Moreover, each runner (12) may include portals (31) which permit four-way entry for the tines (28) of a lift truck and inhibit tipping of the load (14) off the tines (28). As a result, the pallet (10) offers significantly greater safety features, strength and resistence to crushing or compression than known paperboard pallet designs, avoids the significant ecological and economic drawbacks of wooden pallets and can be processed in a paperboard recycling station (44) along with paperboard containers, boxes (48) or the like. Moreover, the system and method for manufacturing the runners (12) with reinforcing inserts (40) overcomes problems of delaminating and separation of the adhesively bonded layers (36, 40) of the runner (12).

Description

REINFORCED PAPERBOARD PALLET AND RUNNER AND ASSOCIATED MANUFACTURING SYSTEM AND METHOD

This is a continuation-in-part of U.S. Patent Application Serial No. 09/629,530 filed July 31 , 2000 which in turn was a continuation-in-part of U.S. Patent Application Serial No. 09/182,263 filed October 29, 1998 and issued as U.S. Patent No. 6,095,061 on August 1 , 2000. Each of these patents/applications are hereby incorporated by reference in its entirety. Background of the Invention

This invention relates to a runner and pallet constructed therefrom for use in the storage and/or transport of goods and, more particularly, to a recyclable reinforced pallet and runner design as well as the associated manufacturing system and method.

For many years, various types of objects have been used to separate and support loads that are stored and transported generally in a stacked arrangement. The equipment that is primarily used for performing this stacking arrangement is a front end loader, lift truck or forklift truck which raises the individual loads so that they can be stacked one on top of the other or on a rack. To separate the loads from each other, off of the rack or off of the floor, a pallet or one or more spacers, risers or runners are positioned beneath the load so as to allow space for the insertion of the forks of the lift truck or the like for moving and positioning the loads for storage or transportation.

Generally, the load supporting pallets, runners and the like are used in large manufacturing and industrial plants, warehouses, wholesale and retail establishments and wherever merchandise, food products and other articles are to be lifted and carried from one location to another. Typically, these pallets or the like are mainly made from wood and consist of platforms having parallel runners longitudinally and/or transversely secured to their undersides by means of nails, staples, strappings or other suitable fasteners. Such wooden pallets in the past have been found to be quite satisfactory in many regards for their intended use in the shifting, transportation and storage of materials and articles from one location to another. There are many advantages of wooden pallets. Wood is extremely strong on a weight basis, and machinable with standard cutting, ripping and other forming techniques. Furthermore, wood will not lose its strength in conditions of high heat, moisture and humidity.

Wood, however, has several major disadvantages. Increasing environmental awareness has become a significant factor in the packaging, transportation and shipping industries. Wood is difficult to readily recycle and, hence, many wood packaging or pallet components are finally disposed in landfills. Available landfill sites, however, are becoming full and are being closed. If landfill disposal is even available, significant fees for dumping such bulky materials are becoming prohibitive. As a result, many customers of manufacturers of heavy durable goods are prohibiting the use of wood pallets. Wood pallets also are very cumbersome, are unwieldy and take up unnecessary and valuable space in conveyances, warehouses and other places of storage. As transportation costs have risen, the concept of moving wood pallets back and forth for reuse, which has always been a burden on the industry, has become economically prohibitive.

In international shipment of goods, wooden pallets present additional environmental problems because they tend to serve as hosts for germs and bugs. As a result, pallets are often quarantined or burned upon arrival in another country according to governmental regulations or general precautionary practices to avoid the spread of undesirable insects, bugs or germs. This has proven to be very costly and a significant economic drawback to wood pallets.

The Wall Street Journal recognized the many significant problems associated with wooden pallets in an article entitled "As Old Pallets Pile Up, Critics Hammer Them as a New Eco-Menace" and published April 1, 1998. According to that article, there are purportedly 1.5 billion pallets in the U.S. and about 40 percent of domestic hardwood lumber goes into pallets. However, a third of U.S. landfills won't take pallets. Purportedly, more than 1 million forest acres are chopped every year for pallets, skids or the like. Cost for the wood to make the pallets is increasing and the available supply of wood is decreasing.

Loads on a pallet are often transported within a warehouse or other facility on a conveyor or rollers. Commonly, wooden pallets splinter and jam the rollers of the conveyor and thereby damage the conveyor and interrupt the movement of the goods in the warehouse. The use of wood pallets on such conveyors has become so problematic that many facilities prohibit their use _ _

on roller conveyors and mandate that the load be transferred to another type of pallet for use on the conveyor or the conveyor not be used at all. Quite evidently, this is very inefficient and time consuming and a significant disadvantage for the continued use of wood pallets.

Wood pallets offer excellent strength and durability, but even these desirable qualitites have proven to be, at best, questionable justification for the continued use of wooden pallets.

To avoid some of these objections to the use of wood pallets, alternative pallet designs have been made from materials such as corrugated paperboard, scrapped paperboard, plastics, aluminum and other materials. While solving certain problems associated with wood pallets, use of alternative materials to date has only provided additional problems. Known corrugated paperboard pallets provide lightweight, inexpensive alternatives to conventional wooden pallets for some applications, but their strength and rigidity under static and dynamic loading is insufficient to permit wide spread general usage for all types and distribution of goods. Such pallets often have excessive deflection and lack beam strength, which causes their sagging under loads, thereby making the handling, stacking and racking of the pallets impractical and even dangerous. Commonly, loads are mounted upon spaced beams of a rack and the weight of the load is concentrated on the pallet at the beam. Many so called improved pallet designs do not offer the strength necessary to withstand buckling, crushing or compression when placed upon a rack under a load. A suitable pallet for use on a rack must provide minimal compression at the beams of the rack and zero to minimal deflection between the beams of the rack. Known paperboard pallets do not meet these compression and beam strength criteria for rackability.

Strength requirements for known paperboard pallets and runners have generally been inadequate. Moreover, when the pallet or runner approaches and exceeds the failure criteria, no warning or indication of the impending failure is typically evident. In other words, as a load is transported, moved or stored on a pallet or runner and exceeds the strength limit for the pallet or runner, occurs without a warning or opportunity to replace the various components.

Additionally, known paperboard pallet designs typically become compressed, crushed, milled off or damaged when used under a load being transported on a roller conveyor. Moreover, corrugated paperboard, for instance, may lose up to 50 percent of its stacking strength during conditions of high humidity and moisture when the paperboard absorbs atmospheric moisture and the like.

As loads are transported on the tines of a forklift or lift truck, the ability to insert the tines under the load from any direction is a significant convenience for the forklift operator. A so called four-way entry to the pallet by the tines of the lift truck or the like is common in the Grocery Manufacturers Association (GMA) type of pallets. To provide four-way entry, some runners include notches which are open to the bottom face of the runner to provide entry of the tines on the lift truck into the runner for lifting the pallet as is shown in the present inventor's U.S. Patent No. 6,095,061. However, if the tines of the forklift or lift truck are not properly positioned in the notches to lift and transport the load or the load is unbalanced, the load could potentially tilt and fall off of the tines. As such, many manufacturers and/or operators often add stringers along the bottom open face of the notches in an effort to stabilize such loads supported on the tines and inhibit the load from tipping or falling off. Nevertheless, stringers of this type typically cannot be added to wood runners or are often ineffective, particularly for heavily loads that could be easily damaged, torn or dislodged during use thereby becoming ineffective for their intended purpose.

Thus, there is an increasing need for pallets which are economically and ecologically feasible. However, an acceptable pallet must possess the strength to support their intended loads particularly on a rack or conveyor and must be sufficiently durable to withstand repeated use including being lifted with a lift truck or the like while loaded. Further, desirably the pallet must resist deterioration by the elements of the weather. Moreover, an acceptable pallet must be competitively priced in the marketplace.

A solution to many of these problems is disclosed in applicant's own prior U.S. Patent No. 6,095,061 which discloses a reinforced, rackable and recyclable pallet and runner. The pallet/runner design disclosed in the '061 patent is light weight and provides significant strength and increased load bearing capability and resistance to compression and crushing while still providing the significant advantages of being entirely processable in a paperboard recycling system or the like for convenient, economical and ecological disposal.

The '061 patent discloses a pallet which includes at least two spaced generally parallel runners and each of the runners is constructed of a number of layers of double wall or double face corrugated paperboard glued together in face-to-face orientation with the flutes of the corrugations being generally aligned in a generally vertical direction. Each of the runners also includes at least one generally vertically oriented reinforcing insert positioned between adjacent layers of the corrugated paperboard. One method for manufacturing such a runner is to laminate layers of corrugated paperboard one on top of another in face-to-face relation with the reinforcing insert or inserts positioned therein. The various layers of paperboard and reinforcing insert may be adhered in a face-to-face relation by an adhesive commonly known in the industry to form the billet. Typically, the billet of sheets or layers of corrugated paperboard and reinforcing insert is then stacked with similar billets one on top of another, typically four to six high, and compressed in an effort to bond the various layers in the respective billets to one another. After compressing the multiple billets in a single batch process, the individual billets are then sawed or cut into the individual runners for ultimate use or incorporation into a pallet.

However, applicant discovered that during the production of the runners according the '061 pallet and the above described method, frequently the adjacent layers of paperboard separate one from another and/or from the reinforcing insert particularly at the lateral ends of the runners. Increased pressure on the multiple billets, increased adhesive volume and alternative adhesives did not significantly improve the situation or minimize the occurrence of runner separation. Therefore, it is apparent that there is a need in the industry for a pallet and/or runner which satisfies these and other criteria and overcomes the associated disadvantages and shortcomings of known pallet and runner designs. Additionally, a need exists for an improved method and associated system for manufacturing paperboard pallet runners that have at least one reinforcing insert that avoids the problem of delaminating or separation of the adjacent layers of glued materials.

Summary of the Invention

The improved runner and pallet constructed therewith overcomes the above- described disadvantages of wood pallets and pallets or runners made from alternative materials known in the shipping, packaging and container industries. Advantageously, the pallet and runner _ _

design according to this invention is economically feasible while being lightweight and providing significant strength and increased load bearing capability and resistance to compression or crushing so that the pallet/runner can support a load on a rack or conveyor. Importantly, the pallet/runner design of this invention, while providing these significant advantages over know palle1j unner designs, is also entirely processible in a paperboard recycling system or the like for convenient, economical and ecological disposal.

Specifically, a pallet according to a presently preferred form of this invention includes at least two spaced generally parallel runners and each of the runners is constructed of a number of layers of double wall or double face corrugated paperboard glued together in face to face orientation with the flutes of the corrugations being generally aligned in a generally vertical direction. Each of the runners also includes at least one generally vertically oriented reinforcing insert positioned interiorly of the runner between adjacent layers of the corrugated paperboard.

Furthermore, in still other presently preferred embodiments, the runner may include a band with a number of nylon, polyester or other material strands situated between the adjacent layers of the corrugated paperboard or incorporated into the various layers of the corrugated paperboard during manufacturing. The band may be used in addition to or as an alternative to the reinforcing inserts. The band is primarily added to the runner to minimize catastrophic rupture, tearing or failure of the paperboard runner as it approaches its maximum load limit. For example, runners which include such a band would begin to sag as they approach they load limit while runners without such a band would fail without warning or notice or opportunity for replacement of the pallet or runner.

Each of the runners preferably includes at least two spaced notches or portals with the respective notches or portals being aligned with one another so that the tines of a lift truck or the like can be inserted therein in a direction generally perpendicular to the runners for lifting the pallet and the load supported thereon. The runners are spaced and generally parallel so that the tines of the lift truck can alternatively be inserted generally parallel to the runners for lifting the pallet and the load and thereby providing what is known in the industry as four-way entry into the runner. The notches in the runner are generally open to the bottom surface of the runner; whereas, in an alternative embodiment, the portals are formed as throughhole in the runners and generally _ _

perpendicular to the adjacent layers of paperboard. The portals provide a safety feature in that the pallet is inhibited from tipping off of a forklift while picking up pallets with the tines inserted in the portals. Moreover, the portal configuration provides increased strength relative to the open bottom notches disclosed in U.S. Patent No. 6,095,061. A pallet constructed with the above-described runners may also include a generally planar upper deck sheet joined to an upper surface of each of the runners and a generally planar lower deck sheet generally parallel to the upper deck sheet and joined to a lower surface of the runners. Alternatively, the upper deck sheet may include a plurality of sidewalls each projecting generally upwardly from a perimeter thereof to define a tray atop the runners to contain the load on the pallet.

The runners may be used separately from the pallet construction. As such, a deposit of adhesive in a presently preferred form is applied to the upper surface of the runner to secure the runner, at least temporarily, to the lower surface of a load to thereby enable the load to be lifted by a lift truck and stored on a rack or the like. A significant advantage of the pallet/runner design according to this invention is that all of the components of the pallet/runner are entirely processible in a paperboard recycling system while still providing strength and stability for use under a load on a rack or conveyor. In prior pallet designs, wood components used either exclusively or in combination with paperboard or other materials prevented the pallet/runner from being processed in a paperboard recycling system. When a shipment of goods or the like is received by a customer, the paperboard boxes or cartons containing those goods are commonly disposed of in a paperboard recycling station. However, the associated pallet/runner was shipped to a landfill or the wood components were manually separated from the other materials. Advantageously, the pallet/runner design of this invention can be deposited into the recycling system along with the cartons or boxes to provide an economical and ecological disposal of the pallet/runner without the labor intensive task of separating the various materials.

Commonly, wood pallets must be quarantined upon arriving at international shipping destinations; whereas, primarily paperboard pallets such as the present invention are not required to be quarantined to avoid the spread of regional diseases, harmful insects or the like. _ _

Various commercial consumers have specifically identified a need for a pallet which can be: 1) placed in a corrugated waste bailer or recycling station at each store so that the components thereof can be processed and sold for recycling along with the used paperboard boxes and other containers commonly processed therein; 2) strong enough to be stored in racks in the same manner as wooden pallets; and 3) has the same four-way entry feature as a wooden pallet. Importantly, these objectives must be obtained in an economical manner to offer a commercially viable alternative to wood pallets. The present invention satisfies these and other requirements.

Wood pallets are typically competitively priced at about $7.50 per pallet; whereas, estimates for the pallet of this invention are very economical at about $6.00 to $6.50 per pallet. Moreover, the pallet/runner according to this invention is very lightweight, on the order of about 17 to 18 pounds per pallet thereby providing for easy maneuvering and handling thereof.

While still being lightweight, the pallet/runner, due in large part to the reinforcing insert and/or band and the flute orientation of the corrugated paperboard, provides significant strength and load bearing capability while resisting compression or crushing. While the chipboard, fiberboard, linerboard, Kraft and paperboard are materials of the reinforcing insert that are common to the shipping, packaging and container industry, particleboard and hardboard provide significant strength to the runner and are materials not typically known in those industries. Particleboard and hardboard are commonly used in the building or construction industry. Furthermore, the hardboard is the most preferred reinforcing insert material because it is primarily a wood fiber based component, it can be die cut, laminated, sawed or otherwise shaped as is required, although such techniques are not commonly employed in the building industry for hardboard. Additionally, hardboard and the other materials for the reinforcing insert are each resistant to the absorption of water and moisture or the like and, therefore, the strength of the runner/pallet does not significantly degrade when exposed to these conditions unlike known primarily paperboard pallet or runner designs.

The corrugated paperboard of the runner offers compression resistance and alignment stability such that the runner does not easily twist, bend, buckle or turn when loaded with a non-vertically aligned load. However, the corrugated paperboard offers little or no beam strength to the runner design. As such, known corrugated paperboard runners deflect dramatically _ _

and/or fail when placed on the beams of a rack under load. The reinforcing insert of hardboard or the like provides beam strength and resistance to compression for the pallet/runner but offers very little alignment stability to the pallet/runner. Therefore, this invention advantageously combines these two components into a pallel/runner design which offers alignment stability, beam strength and compression resistance.

As a result, the pallet/runner of this invention overcomes the significant disadvantages of wood pallets while offering an ecological and economical alternative that provides considerable strength and weight bearing capability so that loads can be easily placed on a rack or the like without compression or crushing of the pallet/runner. The entire pallet/runner can be processed in a paperboard recycling station for ecological and convenient disposal thereof and offers a safer alternative to known pallet/runner designs by avoiding catastrophic failures without warning and minimizing the opportunity for the runner supported load to tip off of the tines of a lift truck.

The improved method and associated system for manufacturing a runner adapted to support a load during transit and storage by itself or in combination with a pallet likewise overcomes the above-described disadvantages. Advantageously, the manufacturing method and system for a runner according to this invention economically, efficiently and reliably produces a runner having a number of layers of corrugated paperboard and a reinforcing insert therein, such as that shown in U.S. Patent No. 6,095,061. Moreover, the improved manufacturing method and system produces a runner that does not delaminate or separate after the billet is constructed.

Specifically, a presently preferred method of manufacturing a runner according to this invention includes juxtaposing a number of layers of corrugated paperboard together in which each layer of paperboard has generally parallel flutes and a pair of spaced faces. Each of the adjacent layers of paperboard are aligned in face-to-face relation and an adhesive is applied between the confronting faces of the adjacent layers of paperboard. At least one layer of a reinforcing insert is interposed between a pair of adjacent layers of corrugated paperboard. Advantageously, the reinforcing insert is recyclable and is most preferably hardboard or particleboard. The reinforcing insert is similarly oriented with respect to the layers of paperboard _ _

and in face-to-face relation therewith. Adhesive is applied between the confronting faces of each layer of the reinforcing insert and the adjacent layers of paperboard to form a billet.

Pressure is then applied to the billet in a direction generally perpendicular to the faces of the layers of paperboard to thereby bond the adhesive to the respective faces and adhere the layers together. Advantageously, the present invention benefits from the discovery that the layers of paperboard commonly have a degree of inherent curvature or warp and are not strictly planar layers. While pressure was applied to a number of billets in a stacked relation previously, having the reinforcing insert in each of the billets inhibits or prevents the pressure applied at the top and bottom of the multiple billet stack from transmitting through the entire stack to achieve optimum face-to-face contact between the warped layers of paperboard and adjacent layers. The slightly warped configuration of the paperboard is inherent in the material. However, typically the reinforcing insert of hardboard, particleboard or the like is not warped.

One of the many advantages that the reinforcing insert provides to the runner is significant strength and load bearing capability while resisting compression or crushing of the runner. While these characteristics of the reinforcing insert are beneficial to the ultimate utility of the resulting runner, these characteristics also minimize the effectiveness of the pressure applied to a stack of multiple billets during prior manufacturing practices. The pressure applied to the stack of billets was not transmitted through the various layers to overcome the warp of the corrugated paperboard layers because of the reinforcing inserts. Therefore, proper face-to-face contact between various adjacent layers of the paperboard and reinforcing insert was not obtained in prior manufacturing operations. As such, the adhesive between such layers of paperboard and adjacent layers of paperboard or reinforcing insert did not effectively bond the layers together which ultimately resulted in delamination or separation of the runner at those locations. However, with the present invention, pressure is applied to only a single billet or a limited number of assembled layers to thereby achieve increased face-to-face contact and adhesive bonding between the adjacent layers. Applying pressure to only one billet or a limited number of layers allows the assembly process to effectively achieve adequate face-to-face contact to allow adequate bonding of the adhesive. The reinforcing insert does not detrimentally _ _

minimize the ability of the pressure applying process to overcome the slight warp in the paperboard layers. Therefore, the warp in the paperboard layers is effectively overcome by the pressure and adequate face-to-face contact is achieved to avoid delamination and separation of the resulting runner. Ultimately, the bonded billet of paperboard and reinforcing insert layers is cut or sawed in a direction generally perpendicular to the layers to separate individual runners from the billet for use directly on the load or as part of a pallet during the storage and shipping and goods.

The associated system for manufacturing a runner according to a presently preferred embodiment of this invention includes a pair of gluing stations for applying adhesive to at least one face of selected layers of paperboard and reinforcing insert. One of the gluing stations is utilized for applying adhesive to the paperboard and the other gluing station applies adhesive to the reinforcing insert layers. Downstream from the gluing stations is a set-up station is provided to arrange and juxtapose the various layers of paperboard and reinforcing insert in face-to-face relationship to form a billet. The system includes at least one pressing station down stream from the set-up station for applying pressure to each of the billets individually or to a limited number of layers. Once again, the pressure is applied in a direction generally perpendicular to the layers of paperboard over substantially the entire surface area of the billet. Each pressing station is adapted to apply pressure to one or a limited number of billets at a time to thereby overcome at least some of the warp in the paperboard layers and achieve increased face-to-face contact and adhesive bonding between the adjacent layers. A cutting station which in one embodiment includes a number of parallel circular saw blades spaced one from another is located downstream from the pressing stations. The cutting station cuts the individual billets in a direction generally perpendicular to the layers of paperboard and reinforcing insert to separate the individual runners. The system also includes a mechanism for transferring the various layers of paperboard, reinforcing insert and billets to and between the respective stations in the form of roller conveyors, wheeled carts on rails or the like.

As a result of the improved manufacturing system and associated method for producing recyclable paperboard runners with reinforcing inserts according to this invention, delamination and separation of the resulting runners is avoided. As a result, the manufacturing operation is significantly more efficient, effective and reliable while minimizing ways to end defective runners as a result of the benefits of overcoming the slight warp inherent in the layers of corrugated paperboard to achieve appropriate face-to-face contact and adhesive bonding in the runner.

Brief Description of the Drawings

The objectives and features of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

Fig. 1 is a perspective view of a presently preferred embodiment of a pallet supporting a load on a rack with a portion of the load and an upper deck sheet of the pallet being broken away to expose the runners of the pallet;

Figs. 1 A and 1 B are each perspective views of alternative embodiments of the pallet according to this invention with a tray containing a load shown in phantom while the pallet and load are being transported on a conveyor; Figs. 2 and 2A are cross-sectional enlarged views of a portion of a pallet including alternative embodiments of a runner according to this invention;

Fig. 3 is a perspective view of individual runners being adhered to a bottom surface of a load;

Fig. 4 is schematic representation of the pallet, runner and boxes or cartons being processed in a recycling station;

Fig. 5A is a perspective view similar to Fig. 3 with a further alternative embodiment of a runner according to this invention;

Fig. 5B is a cross-sectional view taken along line 5B-5B of Fig. 5A of that runner embodiment; Fig. 6 is a perspective view of a stack of layers of corrugated paperboard showing inherent warp in the layers of paperboard;

Fig. 7 is a side elevational view of a stack of billets under pressure according to a prior art manufacturing operation in which selected layers of paperboard are not compressed into face to face contact with the adjacent layers; _ _

Fig. 8 is a side elevational view of a billet according to this invention under compression in which the inherent warp of the paperboard layers is overcome to thereby achieve face-to-face contact over substantially the entire surface of the layers;

Fig. 9 is a top plan view of a system for manufacturing a runner according to one embodiment of this invention;

Fig. 10 is a side elevational schematic view of a gluing station of the system of Fig. 9;

Fig. 11 is a top plan view of a billet used to manufacture runners according to one embodiment of this invention; and Fig. 12 is a top plan view of an alternative embodiment of a system for manufacturing the runner according to this invention. Detailed Description of the Invention

Referring to Fig. 1, a presently preferred embodiment of a pallet 10 according to this invention is shown. The pallet 10 includes a plurality, three of which are shown in Fig. 1 , of generally parallel runners 12. It will be readily understood that the pallet 10 supports a load 14 and may include two, four (Fig. 1 A) or another number of runners 12 within the scope of this invention. The runners 12 are sandwiched between an upper deck sheet 16 adhered, preferably by adhesive or the like, to an upper surface of each of the runners 12 and a lower deck sheet 18, likewise adhered by adhesive or the like, to a lower surface of the runners 12. The lower deck 18 sheet contributes to the structural integrity of the pallet 10 when rolling down the rollers 20 of a conveyor 22, as shown in Fig. 1A, without crushing or collapsing the pallet 10 under the load 14. The lower deck sheet 18 as such aids in the alignment of the runners 12 for proper vertical orientation while used on the conveyor 22. However, in certain applications, it would be understood that the lower deck sheet 18 and/or the upper deck sheet 16 may be eliminated as shown in Fig. 1 B. The pallet 10 supports the load 14 during transportation of the load 14 or storage thereof, for example, on the spaced beams 24 of a rack 26 such as that shown in Fig. 1. Typically, the beams 24 are spaced about 36 inches apart and in some applications are 42 inches apart and extend generally parallel to one another and perpendicular to the runners 12 in the pallet 10. The runners 12 are spaced and generally parallel to one another so that tines 28 of a lift truck (not shown) or the like may be inserted between the runners 12 below the upper deck sheet 16 and above the lower deck sheet 18 for lifting, maneuvering and/or transporting the pallet 10 and load 14. Each of the runners 12 further includes a pair of spaced notches 30 which are generally aligned with the notches 30 in the other runners 12 of the pallet 10 and extend the width of the respective runner 12. The notches 30, form of the invention, are open to the bottom surface of the runner 12 and provide for entry of the tines 28 of the lift truck into the runner 12 for lifting the pallet 10 and the load 14 for maneuvering and/or transporting the pallet 10 and load 14 combination. As a result, the spaced runners 12 and notches 30 thereof provide for four-way entry to the pallet 10 by the tines 28 of the lift truck or the like as is common in the popular Grocery Manufacturers Association (GMA) type pallets.

In an alternative runner embodiment, as shown in Figs. 5A and 5B, each runner 12a includes at least two spaced portals 31 which extend entirely through the runner 12a for the insertion of the tines 28 of a forklift, lift truck or the like. The portals 31 are oriented generally perpendicular to the longitudinal axis of each runner 12a and are essentially located between top and bottom surfaces of the runner 12a. Advantageously, the configuration of the runner 12a, as shown in Figs. 5A and 5B, provides a safety feature in that the pallet 10, load 14 and/or runner 12a cannot tip off of the tines 28 of a forklift or lift truck which is a common problem when picking up loads with open bottom notches as shown in prior pallet and runner designs. The portion of the runner 12a beneath the portal 31 provides a more secure and stable runner and pallet design so that an unevenly distributed load on the tines 28 of the forklift will not tip or fall off of the tines 28 as is possible with the open bottom notch pallet design. Moreover, when a forklift or lift truck suddenly stops or accelerates, the load 14 is stabilized on the tines 28 as a result of the tines 28 being inserted into the portals 31. Moreover, runners constructed with the portals 31 have been tested to be about 7 percent stronger than those with open bottom notches 30. The lower portion of the runner below the portal 31 was completely in tact even after a failure was sensed in the testing procedure. As such, when in use, the pallet 10 with such runner 12a would remain functional and not have fallen through the rack which provides a significant safety feature since one concern with known paperboard pallets is a lack of historical safety data.

Preferably, the portal 31 would be laser cut or stamped out of the individual layers of paperboard which would then be sandwiched together to construct the runner 12a. Portals 31 of this type are commonly not manufactured in wooden runners or pallets because of the difficulty in drilling or sawing such throughhole or portals in the wood without damaging the runner and resulting in excessive scrap.

It should be readily appreciated that the runner 12a can be utilized with a pallet of any desired design or configuration as well as upper and/or lower deck sheets 16, 18 or in combination with other such runners 12a and applied directly to the load 14 as shown in Fig. 5A. As shown in Figs. 1 A and 1 B, the pallet 10 is also useful for the movement of the load 14 on the conveyor 22 or the like. The pallet 10 may support the load 14 on rollers 20 of the conveyor 22 mounted for rotation between spaced generally parallel side rails 32 of the conveyor 22. Preferably the runners 12 of the pallet 10 are oriented generally perpendicular to the rollers 20 of the conveyor 20. The pallet 10 is advantageously useful for transferring the load 14 on the conveyor 22 with the lower deck sheet 18 as shown in Fig. 1 A or without the lower deck sheet as shown in Fig. 1 B. Typically, the lower deck sheet 18 is only included when the pallet 10 is to be used on the roller conveyor 22. Pallets 10 manufactured according to this invention without the lower deck sheet 18 can be nested with one another for space efficient, compact shipment of the pallets 10 when not in use.

An alternative embodiment of the upper deck 16 sheet as shown in Fig. 1A, may include a plurality of upwardly standing sidewalls 34 which are folded from the material of the upper deck sheet 16 to extend around the perimeter thereof. The upper deck sheet 16 and the upwardly standing sidewalls 34, in combination, define a tray which is particularly useful in containing a non-unitized load or the like.

In one embodiment, each runner 12 is approximately 48 inches in length, 3.5 inches in width and 3.5 inches in height. Each notch 30 is spaced approximately ten inches from the nearest end of the runner 12, and is approximately 9.75 inches in length at the lower face of the _ _

runner 12, has a height of approximately one inch and tapers upwardly to a length of about 8.5 inches at an upper surface thereof.

In one embodiment, each runner 12a is approximately 48 inches in length, 3.5 inches in width and 3.5 inches in height. Each portal 31 is spaced approximately 8 inches from the nearest end of the runner 12a and is approximately 9 inches in length and spaced approximately 7/8 inch from the top and bottom surfaces of the runner 12a. Each portal 31 has a height of approximately 1.75 inches. The upper and lower deck sheets 16, 18 each measure approximately 40 inches by 48 inches and the upstanding sidewalls 34 of the tray configuration of the upper deck sheet 16 shown in Figs. 1A and 1 B are approximately 4 inches in height. The flutes of the upper and lower deck sheets 16, 18 are oriented perpendicularly to the runners 12 or 12a.

Referring to Figs. 2 and 2A, cross-sectional views of alternative embodiments of the pallet 10 and one of the runners 12 thereof are shown in cross section. Specifically, in Fig. 2A, the runner 12 is constructed of a plurality of sheets of paperboard 36, each of which are corrugated and built up and adhered in face to face relation by an adhesive such as polyvinyl alcohol (PVA) or another suitable adhesive commonly known in the industry. Each layer of corrugated paperboard 36 of the runner 12 of Fig. 2A preferably is 125# paperboard with type A or type C flutes 38, although any flute configuration or paperboard can be employed with this invention. The flutes 38 in the runners 12 extend generally vertically in single wall or double face corrugated paperboard 38. Preferably, the runner 12 of Fig. 2A includes four plies of double wall corrugated paperboard 36 on either side of a center reinforcing insert 40 which is most preferably a sheet of one-quarter inch thick piece of hardboard. Advantageously, the reinforcing insert 40 is sandwiched interiorly of the runner 12 or 12a and is oriented generally vertically or perpendicular to the deck sheets 16, 18 to provide beam strength to the runner 12. The reinforcing insert 40 may not be located on the exterior faces of the runner 12 or 12a to avoid lamination issues or other potentially detrimental effects. Additionally, locating the reinforcing insert 40 on the interior of the runner 12 or 12a allows the corrugated paperboard 36 layers to assist in maintaining the reinforcing insert 40 vertical when the pallet 10 or runner is loaded. The corrugated paperboard 36 and vertically aligned flutes 38 advantageously provide compression strength to the runner 12, 12a and associated pallet 10 as _ _

well as the alignment of the runner 12, 12a; however, the corrugated paperboard offers little or no beam strength which is provided by the reinforcing insert 40.

Alternatively, locating the reinforcing inserts 40 close to if not on the interior face of the outermost runners 12, 12a of a pallet 10 as shown in Fig. 2 does offer durability advantages. Specifically, operators of lift trucks commonly do not insert the forks of the lift truck parallel to the runners 12, 12a of the pallet 10 either unintentionally or intentionally to rotate the load 14 and pallet 10 or shift slide the pallet 10 on the ground without completely lifting it. Therefore, the leading edges of the forks 28 contact the inner faces of the runners 12, 12a which would puncture and/or damage many known paperboard runner designs. Placement of the reinforcing insert 40 of this invention at or near the inner face of the runner 12, 12a would inhibit and/or prevent the fork 28 from puncturing the runner 12 in this scenario due to the high impact strength and hardness properties of the hardboard and other reinforcing insert 40 materials.

According to the embodiments shown in Figs. 2A and 2, the lower deck sheets 18 are single wall 200#B corrugated paperboard and double wall 200# paperboard of preferably type A or C flutes, respectively. The upper deck sheets 16 of Figs. 2 and 2A are triple wall 1100# corrugated paperboard and double wall corrugated paperboard with type A or C flutes, respectively. The flutes of the deck sheets 16, 18 are oriented generally perpendicular to the longitudinal axis of the runners 12. In certain applications, a layer of hardboard may be used in place of or in addition to the corrugated paperboard of the upper and/or lower deck sheets 16, 18. The reinforcing insert 40 in one embodiment is a rigid or non-flexible member such as hardboard and provides beam strength and resistance to compression for the runner, but offers little or no alignment stability. The reinforcing insert is recyclable and provides added strength such as a piece of chipboard, fiberboard, linerboard, Kraft or paperboard. The reinforcing insert may be a piece of particleboard or a piece of hardboard which provides increased load bearing capability to the runner and associated pallet, increased resistance to compression and is entirely recyclable. However, hardboard is too costly and heavy to be economically and practically used as the only component of the runner/pallet design; therefore, it is advantageously used in combination with paperboard in this invention. _ _

The term "chipboard" is commonly understood in the shipping, packaging or container industry to be a paperboard product generally made from recycled paper stock. "Paperboard" is defined as one of two major product categories in the paper industry and includes materials made on board machines of cellulosic fibers primarily wood, pulp and recycled paper stock. The major types of paperboard are containerboard and boxboard. The other major product group of the paper industry is paper. Another commonly accounted term in that industry is "fiberboard" which is a general term describing combined paperboard typically used for manufacturing containers and may be corrugated or solid. Solid fiberboard is generally considered a solid board made by laminating or pasting two or more plies of container board together. "Linerboard" is paperboard used commonly for the flat outer facings of combined corrugated fiberboard, and the outer plies of fiberboard. "Kraft" designates pulp, paper, or paperboard produced from wood fibers by the sulfate process. Kraft cylinder and Kraft Fourdrinier are also types of Kraft, all of which are collectively referred to as "Kraft".

Hardboard and particleboard are materials commonly used in the building industry. Hardboard is made from wood fibers. In contrast, "particleboard", another building industry material, is made from wood chips and other particles which are not refined into a distinct fiber. The production of particleboard is a "dry" process whereas hardboard on the other hand is produced by both/either a wet and/or dry process.

The term hardboard is not generally known in the container or shipping industry and is typically used as a building material. "Hardboard" is a generic term for panel manufactured primarily from interfelted ligno-cellulose fibers consolidated under heat and pressure in a hot press to a density of at least about 31 pounds per cubic foot. The inter-fiber bond is primarily achieved through the action of the lignin mechanism. Other materials may be added during manufacture to improve certain properties such as stiffness, hardness, finishing properties, resistance to abrasion and moisture, as well as to increase strength, durability and utility. Hardboard is made almost entirely from wood such as wood chips, board trimmings or other scrap which was once waste from the lumber industry and is now routinely saved for processing into hardboard. Generally, hardboard is made from wood chips converted to fibers which are permanently bonded together under heat and pressure into a panel. The binding agent for the hardboard determines the ease _ _

with which the product can be recycled in standard paperboard recycling processes. Hardboard is available from Temple-Inland Forest Products Corp.'s Building Products Division of Dibol, Texas and Georgia-Pacific manufactures and sells a hardboard product code No. 8199911812 that is particularly adapted for use with this invention because of its recycling properties. 5 Corrugated paperboard is generally well known within the packaging industry; whereas, hardboard is common to the construction or building materials industry and applicant has advantageously combined materials from two different industries to solve problems heretofore known with pallets and runners.

Even though hardboard is comprised primarily of wood fibers, it is readily

10 processible in a paperboard recycling station along with the corrugated paperboard and other components of the pallet and runner. Moreover, hardboard does not readily absorb water or moisture such that if the pallet 10 or runner 12, 12a constructed according to this invention is exposed to excessive moisture, the pallet/runner will not fail even though the corrugated paperboard components thereof may absorb the water. Therefore, the strength of the pallet 10 or

15 runner 12, 12a will be maintained until such time as the paperboard components have dried.

An alternative embodiment of the runner 12, 12a is shown in Fig. 2 in which two reinforcing inserts 40, 40, are positioned proximate the exterior faces of the runner 12, 12a with two layers of corrugated paperboard 36 on the exterior most sides of the hardboard and six layers of corrugated paperboard interposed between the reinforcing inserts 40, 40.

20 The pallet 10 and associated runner 12 according to this invention have each been tested to far exceed expected loading requirements and performance of known non-wooden pallet designs. Specifically, single runners 12 according to the embodiment shown in Fig. 2, both with and without the notches 30, were tested according to ASTM Designation D642-76 compression test entitled "Standard Method of Compression Tests for Shipping Containers". Each such runner

25 12 withstood 30,000 pounds, the maximum load possible on the testing machine, without failure or compression. Because 30,000 pounds was the limit for the testing machine, the runner 12 is capable of withstanding an even greater load under this test procedure.

The pallet 10 according to this invention as shown in Fig. 2 with three equally spaced runners 12 and without a lower deck sheet 18 was also tested. The pallet 10 was _ _

positioned to span the beams of a rack spaced 42 inches apart and the load was positioned on a center 12 inch section of the pallet 10 extending the entire 40 inch width of the pallet parallel to the beams and perpendicular to the runners 12 of the pallet 10. The pallet 10 of this design in which the runners 12 did not include the notches 30 was tested in such a manner to withstand 2206 pounds of force with only 1.02 inches of deflection at the mid-point between the beams of the rack. The pallet 10 of this design in which the runners 12 included the notches 30 was tested to withstand 1055 pounds of force with only 0.55 inches of deflection. An additional test of the pallet 10 with four such runners 12 including notches 30 was tested to withstand 1416 pounds of force with only 0.65 inches of deflection. The above-described testing design is considered to be a significantly more severe and demanding test than that typically used for wood pallets; namely, ASTM Designation D1185-94 test entitled "Standard Test Methods for Pallets and Related Structures." This ASTM test method applies the load to the entire length of the pallet spanning the spaced beams of the rack in contrast to the center 12 inch section as in the test performed on the pallet of this invention. This pallet was successfully tested in racks up to 4000 pounds when spanning the entire runner length.

In comparison, a standard corrugated paperboard runner without the reinforcing inserts 40 was tested in a similar manner and failed under the pre-load condition even before the testing machine could register a testing load.

This and other test data on the pallet/runner design of this invention provide ample evidence that the combination of the reinforcing insert 40 and the paperboard layers 36 offer both beam strength and compression resistance for a pallet which is rackable under loads far exceeding expected use conditions. Moreover, the pallet/runner offers these significant advantages in addition to being recyclable and relatively lightweight.

The testing of the pallet/runner of this invention also revealed another benefit of this design. When the runner 12 is loaded to its limit of beam strength when spanning the beams of a rack, the runner produces an audible "pop" or similar sound unlike known non-wood runner designs. The audible sound is a safety feature to this design because even though it has greatly increased beam strength, the "pop" will alert a worker that the runner/pallet is loaded at or above its maximum level and corrective measures are required such as disposal, recycling and replacement of the runner/pallet or removal of some/all of the load is required.

Another feature of an alternative embodiment of the runner 12a and pallet 10 constructed with such a runner 12a according to this invention is shown in Fig. 5B. The runner 5 12a includes a band 35 which may be sandwiched between the individual layers of paperboard 36 in the runner 12a and/or the reinforcing insert 40. Alternatively, the band 35 may be incorporated into the paperboard 36 configuration between the flutes 38 and the facing sheets of the paperboard 36 during manufacture thereof. In one embodiment, the band 35 includes a number of strands 37 of nylon or polyester reinforced material which may or may not include a hot melt adhesive binder

10 39. The band 35 includes a number of strands 37 of nylon, polyester or other similar material at one or more locations in each runner 12a. In one embodiment, the band 35 may be Marotapes™ which is commercially available from Marotech, Inc. in Quebec, Canada or Sesame Tape™ which is likewise commercially available.

Runners 12a which include the band may or may not be significantly stronger than

15 runners 12 without the band of a similar construction; however, runners 12a with such a band deflect, sag or bow before failure and the paperboard did not rupture or tear upon failure. As such, the runners 12a with the band 35, which are utilized in a rack configuration as shown in Fig. 1, would begin to sag or deflect thereby indicating to a user that the runner and/or pallet was approaching its ultimate limit and about to fail and thus provide an indication of the need for

20 corrective measure and/or replacement. Without the band 35, the runners would rupture, tear and/or fail and fall through a racking system thereby potentially damaging the load and other items therebelow.

As used herein, the term "band" includes products such as those described above as well as other woven or nonwoven netting, webbing, mesh, layers, binders or the like which may

25 be inserted or incorporated between the adjacent layers of paperboard or incorporated into one or more individual layers of paperboard as described. Such reinforcing bands may or may not include a hot melt or other adhesive component according to this invention. The band is typically flexible or non-rigid according to certain embodiments and adds tensile strength to the runner to allow it to sag or bend prior to failure without rupturing, tearing or ripping the paperboard components and, as such, provides an early warning indication of an impending failure of the runner and/or pallet.

Referring to Figs. 3 and 5A, the runner 12, 12a according to this invention may be used in combination with other runners 12, 12a and applied directly to the bottom of the load 14. An adhesive 42 (Fig. 3) is deposited onto the upper surface of the runner 12, 12a which in one embodiment is non-drying, non-permanent so that the runner 12, 12a may be selectively applied and removed from the lower surface of the load 14 as required. The adhesive is deposited onto the open flutes 38 of the paperboard 36 and cool air is blown upwardly from the runner 12, 12a through the flutes 38 to cool the adhesive 42. One such adhesive 42 is Instant-Loc No. 346650 which can be commercially obtained from National Starch and Chemical Company in Cincinnati, Ohio. A release agent such as Michem Release Coat No. 40 commercially available from Michelman, Inc. in Cincinnati, Ohio may also be applied.

As shown in Fig. 4, the pallet 10 and/or runner 12, 12a can be processed in a paperboard recycling station 44 for output 46 along with standard paperboard boxes 48, containers or shipping materials,

Referring to Fig. 6, a stack 50 of corrugated paperboard 36 which may be utilized in the manufacture of the runner 12, 12a according to this invention is shown. Fig. 6 demonstrates the fact that corrugated paperboard 36 of the type used in the runner is not strictly planar but inherently includes a degree of curvature or slight warp across the surface area of the faces of the layers of paperboard 36. During the manufacturing operations of the runner, the adjacent layers of paperboard 36 are similarly oriented so that the curvature or warp is oriented similarly with respect to the curvature or warp of the adjacent layers. Nevertheless, the adjacent layers of the corrugated paperboard 36 and reinforcing insert 40 in the runner 12 are not in face-to-face intimate contact. A top plan view of a top layer 36, 40 in a billet 52 is shown in Fig. 11. The layers

36, 40 may include appropriately positioned and configured ovals 54 as shown in Fig. 11. The layers 36, 40 of a billet 32 commonly are about 48 inches by 36 inches so that a number of runners 12 may be cut or separated from the assembled layers of paperboard and reinforcing insert. Cut lines 58 are shown in Fig. 11 to separate inward runners 12 from the billet 52. Referring to Fig. 9, one embodiment of a system 56 for manufacturing the runner 12 according to this invention is shown. The system 56 includes a pair of gluing stations 60, 62. One of the gluing stations 60 is particularly adapted for applying the adhesive to at least one and preferably both of the opposite faces 36a, 36b of each of a number of layers of corrugated 5 paperboard 36. The other gluing station 62 is likewise adapted for applying adhesive to each of the opposite faces 40a, 40b of a layer of reinforcing insert 40. The gluing stations 60, 62 are schematically shown in cross section in Fig. 10 in which a pair of feed rollers 64, 64 are rotationally driven in counter rotation to one another to feed therebetween one of the layers 36 or 40 toward of counter-rotating adhesive application rollers. The outer periphery of each of the

10 adhesive application rollers 66, 66 is ribbed and in contact with wetting roller 68, 68. Each wetting roller 68, 68 is likewise at least partially submerged in a reservoir 70 of adhesive so that upon rotation of the adhesive application roller 66, the wetting roller likewise rotates in contact with the outer periphery thereof. The adhesive is picked up from the reservoir 70 by the wetting roller 68 and is likewise transferred to the outer ribbed surface of the adhesive application roller

15 66 for application to one of the faces 36a, 36b, 40a, or 40b of the layer of paperboard or reinforcing insert 36, 40. A pair of counter-rotating discharge rollers 72, 72 advance the layer 36 or 40 with adhesive thereon from the gluing station 60, 62. In one embodiment, the adhesive gluing stations 60, 62 are commercially available from Osama Technologies, Wood Working Machinery in San Gimignano, Italy. 0 As a result of this invention, the quantity of adhesive applied during the manufacture of the runners 12 is reduced to approximately two to three pounds per thousand square feet from approximately seven to eight pounds per thousand square feet in prior manufacturing operations. In addition to the reduction in the amount of adhesive utilized, the effectiveness of the adhesive is significantly increased because delamination and separation of 5 the adjacent layers of paperboard is eliminated.

An additional feature of the gluing stations 60, 62 according to this invention alternatively includes foaming the adhesive prior to or in conjunction with application to the layers 36, 40 to further reduce adhesive consumption. Alternatively, the adhesive may be sprayed, drizzled or otherwise applied to the faces 36a, 36b, 40a, 40b of the layers 36, 40 within the scope of this invention.

Referring once again to the system of Fig. 9, in one embodiment the gluing stations 60, 62 are oriented approximately 90° from one another in conjunction with a set up station 74 at which the individual layers of paperboard 36 and reinforcing insert 40 are arranged into a billet 52 of layers to be adhesively bonded together. The set up station 74 is located downstream from the gluing stations 60, 62 and upstream from a first transfer mechanism 76 in the form of a conveyor having a plurality of rollers or carts 78 movable on rails 80 on which the billets 32 are transferred to be positioned adjacent one of a number of pressing stations 82 of the system 56. The individual billets 52 are transferred from each cart 78 by a pusher 84 movably mounted on a pair of bars 86, 86 on each cart 78.

To facilitate the efficient manufacture of a large quantity of runners 12, a number of pressing stations 82, six of which are shown in Fig. 9, are included in the system 56. However, it will be appreciated that any number of pressing stations 82 may be utilized within the scope of this invention. The billets 52 are transferred by the carts 78 along the rails 86, 86 to be adjacent one of the pressing stations 56 and are each then transferred by the pusher 84 to the respective pressing station 82 for processing. Each pressing station 82 may take one of a variety of forms for applying pressure to substantially the entire surface area of the upper and lower layers 36, 40 to achieve intimate face-to-face contact between the adjacent layers 36, 40 in the billet 52. Typically, the pressing station 82 may include a lower stationary platen 88 and an upper movable platen 90 for applying pressure to the billet 52 positioned therebetween. Movement of the upper platen 90 and the pressure P₂ applied thereby to the billet 52 may be generated from one or more pneumatic cylinders 92 mounted on a frame 94 in the station 82. In an alternative embodiment of this invention, the pressing stations 82 are arranged vertically one upon another and the billets 52 are delivered by lifts, conveyors or the like to the respective pressing stations 82. The vertical arrangement (not shown) of the pressing stations 82 is particularly advantageous for sites having limited floor space for the system 56. In one embodiment, each pressing station 82 delivers P₂ of approximately 30 pounds per square foot of pressure to the billet 32 to thereby overcome the warp or curvature in _ _

the layers of paperboard 36 and achieve appropriate face to face contact and bonding between the respective adjacent layers 36, 40. Previously, pressure P^ in the amount of as much as 400 pounds per square foot of pressure was applied by platens 88a, 90a to the stack 96 of billets 52 as shown in Fig. 7 and the warp of the paperboard was not flattened out leaving gaps 98 preventing appropriate contact with the adjacent layers of paperboard and reinforcing insert 36, 40 for proper bonding. However, according to this invention, the pressing stations 82 and associated method apply pressure to a single billet 52, limited number of billets 52 or layers 36, 40 to appropriately achieve face-to-face contact while avoiding gaps 98 and overcoming the warp to thereby appropriately bond the layers 36, 40 together. Typically, each billet includes the layers of paperboard and reinforcing insert appropriate for a single runner.

After the pressure is applied to the billets in the individual pressing stations, typically for a duration of about 120 seconds, the individual billets 52 are then transferred to a roller conveyor 100 or an alternative transfer mechanism for transfer to and processing in a cutting station 102. The duration of the pressure on the billets 52 is highly dependent upon the type of adhesive used and should be adjusted appropriately as is know by those skilled in the art. The cutting station 102 includes a series of circular saw blades (not shown) spaced one from another, the spacing of which is determined by the height of the runner, typically 3.5 inches. At least one and preferably multiple runners 12 are severed by the cutting blades from the billet 52 along cut lines 58 as shown in Fig. 11. The cut lines 58 and oval cut-outs in the billet 52 are arranged for cutting the billet 52 to produce the notches 30 in the runner 12. According to the billet 52 shown in Fig. 11 , nine runners 12 are to be cut from the billet 52, each with two notches 30 to provide the four-way entry into the runner 12 or resulting pallet 10. Alternatively, the ovals 54 may be appropriately positioned so that they do not intersect the cut lines 58 and portals in the runners 12 are generated according to an alternative embodiment of this invention. Referring to Fig. 12, an alternative embodiment of a system 56a for manufacturing the runner 12 according to this invention is shown. Features of the system 56a of Fig. 12 that are common to the system 56 of Fig. 9 are identified by like reference numerals. The system 56a includes the pair of gluing stations 60, 62 arranged up stream from the set up station _ _

74 at which the individual layers of paperboard 36 and reinforcing insert 40 are arranged into the billet 52 of layers to be adhesively bonded together.

Downstream from the set up station 74 of the system 56a is a pressing station 82a in the form of upper and lower belts 104, 106 between which the individual billets 52 are serially feed for pressing and processing. Each belt 104, 106 is trained around a pair of end rollers 108 at least one of which is rotationally driven to pass the belt in an endless loop and advance the billets 52 through the pressing station 82a while being pressed. In one embodiment, each belt 104, 106 is driven at a rate of about 25 feet/minute, is 60 inches wide and the associated end rollers 108 are spaced 20 feet apart. A number of intermediate rollers 110 are also provided in the pressing station 82a between each of the pair of end rollers 108. The rollers 108, 110 for each belt are mounted for rotation in a frame that includes a pair of side rails 112 at the opposite ends of the rollers 108, 110. The spacing of the side rails 112 of the upper belt 104 is fixed and preferably adjustable relative to the side rails 112 of the lower belt 106. Preferably, each roller 108 for the upper belt 104 is mounted for rotation on a shaft 114 that extends through a slot 116 in each of the associated side rails 112.

The rollers 108 of the upper belt 104 are weighted to apply the requisite pressure to the billets 52 passing between the belts 104, 106. The spacing between the upper and lower belts 104, 106 is determined by the thickness of the billets 52 being manufactured and the rollers 110 of the upper belt 104 are movable vertically relative to the lower belt 106 to accommodate variations in billet thickness and maintain pressure on the billet 52. Additionally, weights 118 can be added to the outboard portions of the roller shafts 114 of the upper belt 104 to increase the pressure being applied to the billets 52. Once the billets 52 pass through the pressing station 82a they are transferred to the cutting station 102.

The system 56a and associated pressing station 82a affords the continuous production of billets 52 without operator involvement as an additional feature of the invention compared to the system 56 of Fig. 9. Additionally, the transfer of the billets from the set up station 74 and to the cutting station 102 is more easily and efficiently accomplished in the system 56a of Fig. 12. _ _

Therefore, as a result of the system 56 or 56a and associated method for manufacturing reinforced paperboard pallet runners 12 of this invention, the reliability and effectiveness of the manufacturing operation is increased because runners 12 that separate or delaminate from one another are eliminated. Additionally, less force is required during the compression cycle of the manufacturing operation and consumption of adhesive is significantly reduced compared to prior manufacturing operations for runners of corrugated paperboard having warp along with a reinforcing insert.

From the above disclosure of the general principles of the present invention and the preceding detailed description of at least one preferred embodiment, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. For example and without limitation, the various features or aspects of the invention described herein may be utilized collectively, individually and/or in various combinations. Therefore, I desire to be limited only by the scope of the following claims and equivalents thereof.

I claim:

Claims

1. A pallet for supporting a load during transit and storage comprising: a plurality of spaced, generally parallel runners, each of the runners comprising a plurality of layers of paperboard adhered together in a generally vertical orientation; at least two spaced portals in each of the runners, the respective portals of each of the runners being aligned with one another so that tines of a lift truck can be inserted into the portals in a direction generally perpendicular to the runners for lifting the pallet and the load supported thereon, each of the portals being spaced from a bottom surface of the runner to inhibit the pallet and load from tipping off of the tines when inserted therein, the runners being spaced so that the tines can alternatively be inserted generally parallel to the runners for lifting the pallet and load; and a generally planar deck sheet joined to each of the runners.

2. The pallet of claim 1 wherein each of the portals are spaced from a top surface of the runner.

3. The pallet of claim 1 further comprising: a band in each of the runners to inhibit a rupture and indicate a failure of the runner under load.

4. The pallet of claim 3 wherein the band extends longitudinally in the runner and further comprises a plurality of strands.

5. The pallet of claim 4 wherein the strands are selected from the group consisting of nylon and polyester.

6. The pallet of claim 1 further comprising: at least one generally vertically oriented reinforcing insert of a recyclable material positioned interiorly of each runner between adjacent layers of the paperboard, wherein the reinforcing insert in each of the runners provides increased beam strength and resistance to compression of the runner and the layers of paperboard maintain the reinforcing insert in the generally vertical orientation during use and provide resistance to compression of the runner, each of the components of the pallet being entirely processible in a paperboard recycling system.

7. The pallet of claim 6 wherein the paperboard layers are corrugated paperboard with flutes of the corrugated paperboard being generally vertically aligned and perpendicular to the portals and

7. The pallet of claim 6 wherein the paperboard layers are corrugated paperboard with flutes of the corrugated paperboard being generally vertically aligned and perpendicular to the portals and the reinforcing insert is selected from the group consisting of hardboard, particleboard, chipboard, Kraft, fiberboard and liner board.

8. The pallet of claim 1 wherein the deck sheet is an upper deck sheet positioned between a top surface of the runners and the load, the pallet further comprising: a generally planar lower deck sheet joined to a bottom surface of each of the runners.

9. A pallet for supporting a load during transit and storage comprising: a plurality of spaced, generally parallel runners, each of the runners comprising a plurality of layers of corrugated paperboard adhered together with flutes of the layers of corrugated paperboard being generally aligned in a generally vertical direction; at least one generally vertically oriented reinforcing insert positioned interiorly of the runner between adjacent layers of corrugated paperboard; a band in each of the runners to inhibit a rupture and indicate a failure of the runner under load; at least two spaced portals in each of the runners, each of the portals being spaced from a bottom surface and a top surface of the runner to inhibit the pallet and load from tipping off of tines of a lift truck, the respective portals of each of the runners being aligned with one another so that the tines can be inserted into the portals in a direction generally perpendicular to the runners for lifting the pallet and the load supported thereon, the runners being spaced so that the tines can alternatively be inserted generally parallel to the runners for lifting the pallet and load; a generally planar upper deck sheet joined to the top surface of each of the runners; wherein the reinforcing insert in each of the runners provides increased beam strength and resistance to compression of the runner and the layers of corrugated paperboard maintain the reinforcing insert in the generally vertical orientation during use and provide resistance to compression of the runner, each of the components of the pallet being entirely processible in a paperboard recycling system.

10. The pallet of claim 9 wherein the band extends longitudinally in the runner and further comprises a plurality of strands. _ _

11. The pallet of claim 10 wherein the strands are selected from the group consisting of nylon and polyester.

12. The pallet of claim 9 wherein the paperboard layers are corrugated paperboard with flutes of the corrugated paperboard being generally vertically aligned and perpendicular to the portals and the reinforcing insert is selected from the group consisting of hardboard, particleboard, chipboard, Kraft, fiberboard and liner board,

13. The pallet of claim 9 wherein the deck sheet is an upper deck sheet positioned between a top surface of the runners and the load, the pallet further comprising: a generally planar lower deck sheet joined to a bottom surface of each of the runners.

14. A pallet for supporting a load during transit and storage comprising: a plurality of spaced, generally parallel runners, each of the runners comprising a plurality of layers of paperboard adhered together in a generally vertical orientation; a band in each of the runners to inhibit a rupture and indicate a failure of the runner under load; at least one generally vertically oriented reinforcing insert of a recyclable material positioned interiorly of each runner between adjacent layers of the paperboard, wherein the reinforcing insert in each of the runners provides increased beam strength and resistance to compression of the runner and the layers of paperboard maintain the reinforcing insert in the generally vertical orientation during use and provide resistance to compression of the runner, each of the components of the pallet being entirely processible in a paperboard recycling system; and a generally planar deck sheet joined to each of the runners,

15. A runner for supporting a load during transit and storage comprising: a plurality of layers of paperboard adhered together in a generally vertical orientation; at least two spaced portals in each of the runners, the respective portals of each of the runners being aligned with one another so that tines of a lift truck can be inserted into the portals in a direction generally perpendicular to the runners for lifting the load supported thereon, each of the portals being spaced from a bottom surface of the runner to inhibit the pallet and load from tipping off of the tines when inserted therein, the runners being spaced so that the tines can alternatively be inserted generally parallel to the runners for lifting the load.

16. The runner of claim 15 wherein each of the portals are spaced from a top surface of the runner.

17. The runner of claim 15 further comprising: a band in each of the runners to inhibit a rupture and indicate a failure of the runner under load,

18. The runner of claim 17 wherein the band extends longitudinally in the runner and further comprises a plurality of strands.

19. The runner of claim 18 wherein the strands are selected from the group consisting of nylon and polyester.

20. The runner of claim 15 further comprising: at least one generally vertically oriented reinforcing insert of a recyclable material positioned interiorly of each runner between adjacent layers of the paperboard, wherein the reinforcing insert in each of the runners provides increased beam strength and resistance to compression of the runner and the layers of paperboard maintain the reinforcing insert in the generally vertical orientation during use and provide resistance to compression of the runner, each of the components of the runner being entirely processible in a paperboard recycling system.

21. The runner of claim 20 wherein the paperboard layers are corrugated paperboard with flutes of the corrugated paperboard being generally vertically aligned and perpendicular to the portals and the reinforcing insert is selected from the group consisting of hardboard, particleboard, chipboard, Kraft, fiberboard and liner board.

22. A runner for supporting a load during transit and storage which is recyclable in a paperboard recycling system, the runner comprising: a plurality of layers of corrugated paperboard adhered together with flutes of the layers of corrugated paperboard being generally aligned in a generally vertical direction; at least one generally vertically oriented reinforcing insert positioned interiorly of the runner between adjacent layers of corrugated paperboard; a band in each of the runners to inhibit a rupture and indicate a failure of the runner under load, the band extending longitudinally in the runner and including a plurality of strands; and at least two spaced portals in each of the runners, the respective portals of each of the runners being aligned with one another so that tines of a lift truck can be inserted into the portals in a direction generally perpendicular to the runners for lifting the runner and the load supported thereon, each of the portals being spaced from a bottom surface and a top surface of the runner to inhibit the runner and load from tipping off of the tines when inserted therein, the runners being spaced so that the tines can alternatively be inserted generally parallel to the runners for lifting the runner and load; wherein the reinforcing insert in each of the runners provides increased beam strength and resistance to compression of the runner and the layers of corrugated paperboard maintain the reinforcing insert in the generally vertical orientation during use and provide resistance to compression of the runner, each of the components of the runner being entirely processible in a paperboard recycling system.

23. The runner of claim 22 wherein the strands are selected from the group consisting of nylon and polyester,

24. The runner of claim 22 wherein the paperboard layers are corrugated paperboard with flutes of the corrugated paperboard being generally vertically aligned and perpendicular to the portals and the reinforcing insert is selected from the group consisting of hardboard, particleboard, chipboard, Kraft, fiberboard and liner board.

25. The runner of claim 22 further comprising: a deposit of adhesive applied to the top surface of the runner so that the runner can be selectively adhered to a bottom surface of the load in spaced generally parallel relation with similar runners for supporting the load during transit and storage.

26. A runner for supporting a load during transit and storage comprising: a plurality of layers of paperboard adhered together in a generally vertical orientation; a band in each of the runners to inhibit a rupture and indicate a failure of the runner under load; and at least one generally vertically oriented reinforcing insert of a recyclable material positioned interiorly of each runner between adjacent layers of the paperboard, wherein the reinforcing insert in each of the runners provides increased beam strength and resistance to compression of the runner and the layers of paperboard maintain the reinforcing insert in the generally vertical orientation during use and provide resistance to compression of the runner, each of the components of the pallet being entirely processible in a paperboard recycling system,

27. A method of manufacturing a runner adapted to support a load during transit and storage, the method comprising the steps of: juxtaposing together a plurality of layers of paperboard each having a pair of spaced faces, wherein each of the adjacent layers of paperboard are in face to face relation; applying an adhesive between confronting faces of adjacent layers of the paperboard; adding at least one layer of a reinforcing insert each having a pair of spaced faces to the plurality of layers of paperboard, wherein each reinforcing insert layer is similarly oriented with respect to the plurality of layers of paperboard and in face to face relation to at least one of faces of one of the layers of paperboard; applying the adhesive between confronting faces of each layer of the reinforcing insert and the adjacent layer of paperboard to form a billet; and applying pressure to the billet in a direction generally perpendicular to the faces of the layers of paperboard to thereby bond the adhesive to the respective faces and adhere the layers together.

28. The method of claim 27 further comprising: cutting the billet in a direction generally perpendicular to the faces into at least one individual runner.

29. The method of claim 28 wherein the cutting step further comprises: cutting the billet along a plurality of generally parallel cut lines into a plurality of runners.

30. The method of claim 27 wherein the reinforcing insert layer is recyclable and selected from the group consisting of hardboard and particleboard.

31. The method of claim 30 wherein the reinforcing insert layer is positioned interiorly of the billet between layers of the paperboard.

32. The method of claim 27 wherein the paperboard is corrugated paperboard including a plurality of generally parallel flutes, the method further comprising: orienting the flutes of the layers of corrugated paperboard generally parallel to one another.

33. The method of claim 27 wherein the layers of paperboard have at least some warp and the pressure applying step is performed individually on each billet to thereby overcome at least some of the warp and achieve increased face to face contact and adhesive bonding between the adjacent layers of paperboard.

34. The method of claim 27 wherein a plurality of layers of reinforcing insert are added to the plurality of layers of paperboard and the plurality of layers of reinforcing insert are not adjacent to one another.

35. The method of claim 27 wherein the pressure is applied to substantially the entire surface area of the respective faces of outermost layers of the billet.

36. The method of claim 27 further comprising: foaming the adhesive prior to the respective applying steps.

37. The method of claim 27 wherein the adhesive applying steps further comprise applying the adhesive to substantially the entire surface area of the respective faces of the layers.

38. The method of claim 27 wherein the adhesive applying steps further comprise applying the adhesive according to one of the following: spraying the adhesive, applying the adhesive with a roller, and applying the adhesive in a plurality of generally parallel streams of adhesive.

39. The method of claim 27 wherein the cutting further comprises sawing the billet.

40. The method of claim 27 wherein multiple billets are not juxtaposed together during the applying pressure step.

41. The method of claim 27 wherein the applying pressure step further comprises: serially passing each of the billets between a pair of spaced and moving belts.

42. A method of manufacturing a runner adapted to support a load during transit and storage, the method comprising the steps of: juxtaposing together a plurality of layers of corrugated paperboard each having a plurality of generally parallel flutes and a pair of spaced faces, wherein each of the adjacent layers of paperboard are in face to face relation; applying an adhesive between confronting faces of adjacent layers of the paperboard; adding at least one layer of a reinforcing insert each having a pair of spaced faces to the plurality of layers of paperboard; wherein each reinforcing insert layer is recyclable and selected from the group consisting of hardboard and particleboard and is similarly oriented with respect to the plurality of layers of paperboard and in face to face relation to at least one of faces of one of the layers of paperboard; applying the adhesive between confronting faces of each layer of the reinforcing insert and the adjacent layer of paperboard to form a billet; applying pressure to the billet in a direction generally perpendicular to the faces of the layers of paperboard to thereby bond the adhesive to the respective faces and adhere the layers together; wherein the layers of paperboard have at least some warp and the pressure applying step is performed individually on each billet to thereby achieve increased face to face contact and adhesive bonding between the adjacent layers of paperboard and reinforcing insert; and cutting the billet along a plurality of generally parallel cut lines into a plurality of runners.

43. The method of claim 42 wherein multiple billets are not juxtaposed together during the applying pressure step.

44. The method of claim 42 wherein the applying pressure step further comprises: serially passing each of the billets between a pair of spaced and moving belts.

45. A runner adapted to support a load during transit and storage manufactured by the method comprising the steps of: juxtaposing together a plurality of layers of corrugated paperboard each having a plurality of generally parallel flutes and a pair of spaced faces, wherein each of the adjacent layers of paperboard are in face to face relation; applying an adhesive between confronting faces of adjacent layers of the paperboard; adding at least one layer of a reinforcing insert each having a pair of spaced faces to the plurality of layers of paperboard; wherein each reinforcing insert layer is recyclable and selected from the group consisting of hardboard and particleboard and is similarly oriented with respect to the plurality of layers of paperboard and in face to face relation to at least one of faces of one of the layers of paperboard; applying the adhesive between confronting faces of each layer of the reinforcing insert and the adjacent layer of paperboard to form a billet; applying pressure to the billet in a direction generally perpendicular to the faces of the layers of paperboard to thereby bond the adhesive to the respective faces and adhere the layers together; wherein the layers of paperboard have at least some warp and the pressure applying step is performed on only a single billet at a time to thereby achieve increased face to face contact and adhesive bonding between the adjacent layers of paperboard and reinforcing insert; and cutting the billet along a plurality of generally parallel cut lines into a plurality of runners.

46. A system for manufacturing a runner adapted to support a load during transit and shipping, the system comprising: a gluing station for applying adhesive to at least one face of selected layers of paperboard; a set up station downstream from the gluing station for juxtaposing a plurality a plurality of layers of paperboard and at least one layer of a reinforcing insert in face to face relation to form a billet; and a pressing station downstream from the set up station for applying pressure to the billet in a direction generally perpendicular to the layers of paperboard to adhere the adjacent layers of paperboard and the layer of reinforcing insert to each other over substantially the entire surface area of the adjacent faces of the layers.

47. The system of claim 46 further comprising: a cutting station downstream from the pressing station for cutting the billet generally perpendicular to the layers of paperboard and reinforcing insert into at least one runner.

48. The system of claim 46 further comprising a plurality of the pressing stations wherein the layers of paperboard have at least some warp and the pressing stations is adapted to apply pressure to one billet at a time to thereby overcome at least some of the warp and achieve increased face to face contact and adhesive bonding between the adjacent layers of paperboard.

49. The system of claim 46 further comprising a plurality of the gluing stations one of which is adapted for applying adhesive to the layers of paperboard and another of which is adapted for applying adhesive to the layer of reinforcing insert.

50. The system of claim 46 further comprising: a mechanism for transferring the layers of paperboard and reinforcing insert to and between the respective stations.

51. The system of claim 46 wherein the pressing station further comprises: a pair of belts each trained around a plurality of rollers to pass in a loop, at least one of the belts being driven; wherein the belts are spaced from one another and similarly oriented to accept the billets serially fed there between.

52. A system for manufacturing a runner adapted to support a load during transit and shipping, the system comprising: a first and a second gluing station for applying adhesive to at least one face of selected layers of paperboard and reinforcing insert, the first gluing station being adapted for applying adhesive to the layers of paperboard and the second gluing station being adapted for applying adhesive to the reinforcing insert. a set up station downstream from the gluing stations for juxtaposing a plurality a plurality of layers of paperboard and at least one layer of the reinforcing insert in face to face relation to form a billet; and a pressing station downstream from the set up station for applying pressure to the billet in a direction generally perpendicular to the layers of paperboard to adhere the adjacent layers of paperboard and the layer of reinforcing insert to each other over substantially the entire surface area of the adjacent faces of the layers; wherein the layers of paperboard have at least some warp and the pressing stations are adapted to apply pressure to individual billets to thereby overcome at least some of the warp and _ _

achieve increased face to face contact and adhesive bonding between the adjacent layers of paperboard; wherein the pressing station further comprises a pair of belts each trained around a plurality of rollers to pass in a loop, at least one of the belts being driven; wherein the belts are spaced from one another and similarly oriented to accept the billets serially fed there between; and a cutting station downstream from the pressing station for cutting the billet generally perpendicular to the layers of paperboard and reinforcing insert into at least one runner.