Apparatus having paired lifting members for separating stacked pallets

An apparatus for vertically separating stacked pallets a sufficient distance such that each pallet in the stack can be cleaned, with the pallets then immediately restacked after cleaning.

BACKGROUND OF THE INVENTION

This invention relates generally to the field of separating stacked pallets for cleaning or other purposes, and more particularly to the field of separating stacked pallets by vertically expanding the stack, performing the cleaning operation, and re-stacking the pallets.

Vast numbers of pallets are in use in multiple industries. In many instances, the pallets become contaminated or dirty and must be cleaned prior to reuse. The dirty pallets are usually transported and stored in vertical stacks. One common technique for cleaning pallets is to handle each pallet individually by removing them one at a time from the pallet stack, washing or spraying each pallet as it is presented, then restacking the pallets. This is a very time consuming process, since each pallet must be removed from the pallet stack of dirty pallets and a new stack must be created of clean pallets.

There is a need for an apparatus and technique to separate stacks of pallets in a batch process for simultaneous cleaning of the entire stack rather than removing and cleaning each pallet individually. However, because major portions of the pallets' upper and lower surfaces are in direct contact with other pallets when stacked, or because the pallets are shaped so as to nest when stacked, it is not possible to adequately clean the pallet stack in a batch mode using typical washing and spraying techniques. This invention meets the stated need and addresses the problems inherent in the stacked pallets by providing an apparatus that vertically expands the pallet stack, quickly and easily separating each of the pallets in the stack a small but sufficient vertical distance from the other pallets such that the tops, bottoms and sides of the pallets are exposed and can be cleaned quickly and efficiently using spraying equipment. Upon cleaning, the expanded stack of pallets is then immediately contracted into a compact stack for transport.

SUMMARY OF THE INVENTION

The invention is an apparatus for expanding stacked pallets such that each individual pallet is separated a short distance vertically. The apparatus comprises pallet separation means for vertically separating each pallet in the stack, the pallets being temporarily spaced sufficient distance such that no portion of any pallet is in contact with an adjacent pallet and such that any contaminants, dirt or other undesirable substances are adequately exposed for removal by cleaning means for removing the contaminants, such as washing or spraying equipment that directs high pressure jets of fluid onto and between the pallets.

The apparatus comprises a plurality of horizontally-extending pallet lifting members that are linked in vertical orientation. The lifting members comprise horizontally-oriented insertion arm members that fit between adjacent pallets or into apertures in individual pallets, and carriage members, the insertion arm members being insertable into the pallet stack by lateral translation movement. The lifting members are linked by spacing link members that allow successive separation of each lifting member from the adjacent lifting member as the uppermost lifting members are raised. For each pallet there are two opposing lifting members, such that a first lifting member is disposed on one side of the pallet and a second lifting member is disposed on the opposing side of the pallet, the insertion arm members facing inwardly. Each pallet thus has a pair of lifting members. The lifting members are vertically disposed in two opposing and separate arrays, each of the lifting members positioned to correspond to an individual pallet in the pallet stack and linked in vertical manner. Means for raising and lowering each array of lifting members, such as a motorized chain or belt, hydraulic members, or the like, are provided to expand and contract the pallet stack.

Initially, the opposing arrays of lifting members are laterally spaced such that the pallet stack may be placed between the two arrays using a forklift, conveyor or similar means. In the neutral or loading orientation, with the pallet stack having been put into position, the opposing arrays of lifting members are laterally translated against opposite sides of the pallet stack, i.e., brought toward each other, such that the insertion arm members become situated between or mated with the corresponding individual pallets. The uppermost opposed lifting members are then raised, thereby lifting the uppermost pallet from the stack. The spacing link members allow the top pallet to be raised a short distance prior to vertical movement of the second layer of lifting members, thereby separating the pallet from the one below. As the uppermost lifting members and the top pallet continue to rise, the second pair of lifting members and their associated pallet begin to rise. This process is successively repeated until all of the pallets are raised and separated from the adjoining pallets. The cleaning process may then be initiated and all pallets are cleaned simultaneously. Upon completion, the arrays of lifting members are lowered, thereby restacking the now clean pallets for removal from the apparatus.

The invention is a pallet separating apparatus adapted to expand a stack of pallets in the vertical direction such that each pallet is separated a short distance from adjoining pallets and then restack the pallets, the apparatus comprising:

a plurality of lifting members, each lifting member comprising a pair of carriage members, an extended bar member, a mounting flange and at least two horizontally-oriented insertion arm members, and at least one post member positioned on the side of the carriage member;

a plurality of spacing link members each comprising an elongated extension slot, said spacing link members being retained on said post members of adjoining lifting members;

a first array of said lifting members disposed in a first frame assembly and a second array of said lifting members disposed in a second frame assembly;

lateral translation means for reciprocating said first and second frames toward and away from each other;

separating means for raising and lowering each array of lifting members such that vertically adjoining lifting members are separated;

whereby with a stack of pallets positioned between said first and second frame assemblies, said frame assemblies are laterally moved together such that said insertion arm members of said lifting members are inserted into or between individual pallets in said stack, the uppermost set of opposing lifting members are raised, thereby raising the uppermost pallet from the stack and separating the uppermost sets of opposing lifting members from the next adjacent set of opposing lifting members, continuing to raise said uppermost set of lifting members until said extension slots of said link members abut the post members of the next lower adjacent set of opposing lifting members, such that the next adjacent set of opposing lifting members and the next adjoining pallet are raised, and continuing this operation until all said pallets in said stack are separated from adjoining pallets, performing a cleaning operation on the separated pallets, lowering the lifting members and pallets to reform the stack, and separating said first and second frame assemblies.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawings, the invention will now be described in detail with regard for the best mode and the preferred embodiment. The invention is an apparatus and the method of using the apparatus for vertically expanding a stack of pallets. The apparatus comprises pallet separation means for vertically separating each pallet in the stack, the pallets being temporarily spaced sufficient distance such that no portion of any pallet is in contact with an adjacent pallet and such that any contaminants, dirt or other undesirable substances are adequately exposed for removal by cleaning means for removing the contaminants, such as washing or spraying equipment that direct high pressure jets of fluid onto and between the pallets.

The apparatus comprises a plurality of horizontally extending pallet lifting members10that are linked in vertical orientation in a chain-like manner. As shown inFIGS. 1 and 2, the lifting members10each comprise a pair of carriage members14, an extended bar member11, a mounting flange13and at least two horizontally-oriented insertion arm members12, the arm members12fitting between adjacent pallets99or into apertures in individual pallets99, the insertion arm members12being insertable into the pallet stack by lateral or horizontal movement. Each lifting member10is provided with at least one post member15positioned on the side of the carriage member14. The number and shape of the insertion arm members12may vary depending on the design and structure of pallets99.

The lifting members10are linked to each other by spacing link members20, as shown inFIG. 3, that allow successive separation of each lifting member10from the adjacent lifting member10as the uppermost lifting members10are raised. Each spacing link member20comprises an elongated body and an elongated extension slot. The linking members20are retained by the post members15of adjoining carriage members14. Multiple lifting members10and linking members20are joined in this manner to form an extended chain.

The separation functionality is illustrated inFIG. 4. In the neutral or loading orientation, the lifting members10are disposed vertically, the lifting members10resting one atop the other in a stack with the insertion arm members12facing laterally and separated by the required distance for insertion into the pallet stack. As the upper lifting member10is raised, the spacing link member20is stationary until it abuts the post member15of the next lower lifting member10, thereby defining the separation distance between the adjacent lifting members10and raising the lower lifting member10. This process continues for each lifting member10in the lifting member assembly.

For each pallet there are at least four insertion arm members12in order to properly balance the pallet99. One of the lifting members10is positioned in opposition to the other lifting member10, such that a first lifting member10is disposed on one side of the pallet99and a second lifting member10is disposed on the opposing side of the pallet99, the insertion arm members12facing each other. Each pallet99thus has a corresponding pair of lifting members10. The lifting members10are vertically disposed in two opposing and separate arrays61and62, each paired set of lifting members10vertically positioned to correspond to an individual pallet99in the pallet stack. The arrays61and62are mounted within frame assemblies51and52. The frame members51and52are structured to define tracks that allow vertical movement of the lifting members10. Separating means54for raising and lowering each array61and62to separate the lifting members10, such as a motorized chain or belt, hydraulic members, or the like, are provided on frame members51and52to expand and contract the pallet stack. Lateral translation means53for reciprocating the frames51and52, such as for example motorized assemblies on tracks or rollers, are provided such that the two opposing arrays61and62can be moved toward and then away from each other.

In the neutral or loading orientation, the arrays of lifting members10are laterally translated inwardly against opposing sides of the pallet stack such that the insertion arm members12are placed between or mated with the individual pallets99. The uppermost lifting member10of each set is raised, thereby lifting the uppermost pallet99from the stack. Preferably, the lifting members10of one array61are raised into a higher position than the lifting members of the opposing array, so that the pallet99will be raised in a tilted orientation to allow water to more easily drain. The spacing link members20allow the top pallet99to be raised a short distance prior to vertical movement of the next set of lifting members10. As the uppermost lifting members10and the top pallet99continue to rise, the associated link members20are raised until the bottom of the slots21make contact with the post members15of the next lower carriage members14, at which time the second lifting members10and their associated pallet99begin to rise. This process is successively repeated until all of the pallets99are raised and separated from the adjoining pallets. The cleaning process is then initiated and all pallets99are cleaned simultaneously. Upon completion, the sets of lifting members10are lowered, thereby restacking the now clean pallets99for removal from the apparatus after the frame assemblies51and52have been retracted.

It is understood that equivalents and substitutions for certain elements described above may be obvious to those of ordinary skill in the art, and therefore the true scope and definition of the invention is to be as set forth in the following claims.