US3726424A

US3726424A - Pallet

Info

Publication number: US3726424A
Application number: US00130918A
Authority: US
Inventors: Puls J Du
Original assignee: PULS J DU
Current assignee: PULS J DU
Priority date: 1971-04-05
Filing date: 1971-04-05
Publication date: 1973-04-10
Anticipated expiration: 1990-04-10

Abstract

A lift truck pallet is provided with rotatable load supporting means for transferring a load from the pallet in a direction lateral to the direction of insertion of forks therein. The preferred rotatable load supporting means is in the form of rotatable rollers having axes substantially parallel to the direction in which the forks are received in the pallet, and drive means may be provided to rotate the rollers to transfer the load from the pallet to a space located laterally of and adjacent to the pallet.

Description

United States Patent 1191 Du Puis et al.

[ Apr. 10, 1973 PALLET [51] Int. Cl. ..B66f 9/12 [58] Field of Search ..214/620; 108/51 [56] References Cited UNITED STATES PATENTS 2/1952 Stewart ...214/620X 5/1970 MerittetaL... ..214/620 3,292,804 12/1966 Veneman ..214/620 X Primary Examiner-Robert J. Spar Attomey-Fitch, Even, Tabin & Luedeka [57] ABSTRACT A lift truck pallet is provided with rotatable load supporting means for transferring a load from the pallet in a direction lateral to the direction of insertion of forks therein. The preferred rotatable load supporting means is in the form of rotatable rollers having axes substantially parallel to the direction in which the forks are received in the pallet, and drive means may be provided to rotate the rollers to transfer the load from the pallet to a space located laterally of and adjacent to the pallet.

3Claims,3DrawingFigures PATENTEUAPRImm A I $726,424

FIG!

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PALLET The present invention relates to pallets for supporting loads and, more particularly, the invention relates to a pallet for transferring a supported load in a confined area.

A load of merchandise, such as lumber, steel beams, rugs, or other heavy, elongated articles, is often stacked upon a pallet, which is carried by a fork lift truck from one location to another. For example, the palletized load may be transported by the truck from a warehouse loading ramp to a designated position in a row of merchandise. It is particularly desirable to conserve space in the warehouse and accordingly the rows of stacked merchandise are usually closely spaced. However, normal lift truck operation is made exceedingly difficult as the trucks cannot maneuver within the aisles between the rows to emplace or remove merchandise. Heretofore, when the aisles have been too narrow for the lift trucks to maneuver, manual labor has been employed to handle the loads or expensive special fork lift trucks and other equipment have been used which is capable of manipulating the palletized loads within the aisles such that the loads can be transferred laterally into the desired positions in the rows.

An object of the present invention is to provide an improved pallet for supporting and transferring a load.

Another object of the invention is to provide an improved pallet adapted to transfer a supported load in a confined area.

These and other objects of the invention will become apparent upon reference to the following detailed description and accompanying drawings, in which:

FIG. 1 is a schematic representation of a load being transferred within a confined area;

FIG. 2 is a perspective view of a pallet for supporting and transferring the load; and

FIG. 3 is an enlarged plan view of a portion of the pallet shown in FIG. 2.

Very generally, there is illustrated in the drawings a pallet for supporting and transferring a load 18 comprising a frame 12 and a pair of fork receiving pockets 14 into which may be'inserted forks 19 of afork lift truck 15. The fork lift truck may travel in a forward direction, as indicated by the directional arrow A in FIG. 1 or in a direction reverse thereto. With use of the pallet 10, the load 18 may be shifted laterally, at right angles in this instance, to the direction of truck movement with turning of rotatable load supporting means, preferably in the form of rollers 16 joumalled for rotation in the pallet frame to turn about axes substantially parallel to the direction of the forks and truck movement. Means may be provided to turn the rollers 16 to transfer the load laterally from the pallet, and means may be provided for detenting the rollers against rotation while the pallet and load are being transported.

The illustrated pallet 10 is particularly useful in handling loads in confined areas. A load 18, such as lumber, steel beams, rugs, poles, etc., is stacked transversely across the pallet and the palletized load is transported to a location adjacent a row of other merchandise in a warehouse, such as shown in FIG. 1. The load is transferred in a lateral direction from the pallet into a space in the row. The space illustrated in FIG. 1 is adjacent one side of the pallet and located adjacent another wall which would limit maneuvering the lift truck. Accordingly, a fork lift truck 15 used to transport the loaded pallet need not maneuver within an aisle between two parallel rows of merchandise. The fork lift truck proceeds straight ahead in the aisle and stops slightly behind the desired location, whereupon the load, which is at the front of the truck, is transferred laterally from the truck. It should furtherbe appreciated that any standard fork lift type industrial truck can be employed to transport the pallet of the illustrated embodiment and that no special, relatively expensive equipment need be utilized either for transporting the pallet or for unloading it.

The frame 12 of the pallet 10 supports both the pockets 14 which receive the forks 19 of the lift truck 15 and the rollers 16 which permit lateral transferring of the load. The frame 12 is of rigid construction so as to receive and carry a heavy load 18, such as steel beams or lumber, without buckling. The illustrated frame 12 is rectangular in shape and includes a pair of substantially parallel end plates 20 and a pair of substantially parallel side channels 22 connecting the respective ends of the end plates 20. The side channels 22 are shorter in height than the end plates 20. An elongated stiffener 24 is secured to one or both of the end plates 20 to prevent the end plates from buckling. The fork receiving pockets 14 each include apertures 26 formed in the end plates 20 and spaced suitable distances apart to allow the forks 19 of the lift truck 15 to enter. Where the apertures 26 are located in both end plates 20, the fork lift truck can approach and lift the pallet from either of two opposing directions.

The form receiving pockets 14 further comprise elongated channels 29 welded to the end plates 20 with internal openings in the channels alignedwith the apertures 26 in opposite end plates 20. The apertures and the channels are of suitable dimensions to receive the forks 19 of the lift truck 15. Each of the elongated channels 29 extends substantially perpendicular to the end plates 20 and substantially parallel to the rollers 16. This permits the pallet to be lifted and carried in a direction parallel to the longitudinal dimension of the fork receiving channels and rotational axes of the rollers 16. It should be noted that single pocket pallets may be provided when single blade-type lift trucks are employed.

The channels 29 are substantially rectangular in cross-section and each includes a top wall 30,a bottom wall 32, and substantially parallel outer and inner side walls 34 and 36 connecting the top and bottom walls. The walls may be reinforced adjacent one or both ends,

'if desired, and in some instances it may be advantageous to delete the bottom wall. Each fork of the truck used for lifting the pallet is received and is enclosed within the walls, with each fork 19 resting against the underside of the top wall 30 of its respective channel when the pallet is lifted. The flat top wall 30 has the additional function of supporting the load. As aforesaid, the load preferably extends transversely across the pallet. Therefore, the load is supported by the two fork receiving channels 29 and by the two rollers 16, but not by the side channels 22.

The ability to transfer the load 18 laterally from the pallet 10 is especially advantageous when the load is extremely heavy or has been stacked to a great height. In the first instance, the warehouseman may be unable to push and slide a heavy load from an ordinary pallet. In the second instance, pushing a high stacked load from an ordinary pallet may result in the load tumbling to the floor because of the high frictional resistance to sliding between the load and ordinary pallet. With the pallet 10, however, the load may be pushed with the rollers 16 turning as the load moves laterally. Also, the rollers 16 which support the load may be rotated to positively drive the load off the pallet into the selected space. I

Preferably, two rollers 16 are utilized to transfer the load 18 as a pair of rollers provides positive traction and permits unloading in either of two directions. Both of the rollers 16 are positioned in the frame 12 adjacent the respective outer side walls 34 of each of the channels 29. The rollers are accordingly located at opposite lateral edges of the frame 12 and are positioned immediately within the side channels 22. Locating the rollers at the lateral edges of the pallet ensures the transfer of the entire load from the pallet. It should be noted, however, that one roller 16 may satisfactorily transfer a load from the pallet. The rollers 16 are journalled in bearings 38 (FIG. 3) in the end plates 20 to permit nonbinding rotational movement of the rollers. The rollers 16 may be provided with a friction-increasing surface, such as rubber, to better engage and transfer the load.

To rotate the rollers 16 and thus discharge the load from the pallet 10, a drive system 40 may be employed. Preferably, the drive system 40 for the rollers 16 is entirely independent of the lift truck so that specially designed fork lift trucks with extra drive mechanisms are not needed nor are specially designed jigs required for use with the pallet 10.

Preferably, the drive system 40 for the rollers is located externally of the rollers so that the drive system is not damaged when the pallet is being loaded and transported. The preferred external drive system permits the individual pallets to be constructed simply and relatively inexpensively. To this end, a squared-end trunnion 42 extends outwardly from at least one end of each roller 16 beyond the respective end plate 20. The trunnion 42 and its associated roller 16 are rotatable by a ratchet-type wrench 44 having a socket 45 which receives the trunnion 42 and which is operatively connected to an elongated handle 46. Rotation of the roller by the wrench 44 upon turning movement of the handle 46 frictionally transfers the load supported by the roller from the pallet. The drive system may also comprise a ratchet wheel (not shown) mounted either externally on or internally of the roller. In either case, a simple lever or handle 46 is used to rotate the roller. The wrench or simple lever or handle employed to rotate the rollers can be mounted directly to the frame 12 or can be independent thereof. Alternatively, an electric motor can be mounted on the pallet for rotating the rollers 16 through a gear train or other power transmission apparatus.

A detenting means orlock 48 is preferably provided at least at one end of each roller 16 for normally preventing the rollers from rotating and thereupon transferring the load from the pallet 10 while the pallet is being transported by the lift truck 15. At best seen in FIG. 3, the illustrated lock 48 includes a detent pawl 50 which is normally received in one of a plurality of grooves 52 formed in the outer surface of the adjacent roller 16. A torsion spring 54 biases the detent pawl into one of the grooves. More specifically, the torsion spring 54 has one end fastened to the end plate 20 and its other end fastened to a shaft 55 which is journalled for turning in the end plate 20. The shaft 55 is connected to arm 56 of the detent pawl 50 and acts therethrough to bias the pawl 50 into a groove 52. The arm 56 may be pulled outwardly away from the end plate 20 with the torsion spring 54 being compressed and the pawl 50 being moved outwardly from the grooves 52. The roller 16 is thus free for rotation by the drive system 40. The lock 48 is rendered inoperative by twisting the arm 56 when in its pulled out position such that the detent 50 rests on the outer sideof the end plate 20 and is spaced from the roller 16.

A brief description of a use of the pallet will now be given. After the pallet 10 has been loaded, the fork lift truck 15 is maneuvered such that its forks 19 are respectively positioned within the pockets 14. The truck lifts the pallet and proceeds down an aisle until the pallet, which is at its front end, is adjacent a space in a row of merchandise. It is unnecessary to maneuver the truck to place the pallet in the space. The locks 48 are released, and then the drive system 40 is employed to rotate the rollers 16 to transfer the load 18 from the pallet into a space, as shown in FIG. 1. Therefore, the load can be placed in a space in the row of merchandise although the rowsare so closely spaced that a standard industrial truck could not manipulate palletized loads to place them directly into the selected locations.

It should be appreciated that the load couldalso be transferred from the pallet to a second pallet positioned in the space in the row. This makes it easier to remove the load from the space when it is desired to use the merchandise. When employing a second pallet, the rollers of both pallets are preferably rotated in the same direction to efficiently transfer the load between the pallets. To return the load to a pallet located in the aisle, the rollers of both pallets are rotated in the same direction toward the aisle, whereupon the load is trans ferred onto the pallet in the aisle.

Thus, the present invention provides an improved pallet for laterally transferring a load therefrom and within a confined area.

While the pallet 10 has been described in connection with one use, as in confined areas, the pallet maybe advantageously employed in a number of other situations. For example, in a lumber yard, a stack of lumber may be spanning spaced blocks with opposite ends resting on the blocks. The pallet 10 carried by a lift truck 15 may be inserted into the space beneaththe stack and between the blocks and then the stack may be lifted from the blocks and transported on the pallet to another location at which the stack may be pushed from or driven from the pallet 10 with turning of the rollers 16.

The stack of lumber on the pallet 10 may be transferred in a lateral direction to various receivers such as, for example, a conventional split bed truck. This kind of truck is usually provided with a flat, generally horizontal bed having two sets of spaced apart, transversely extending conveyor rollers. Each set of rollers form a roller conveyor which extends from the rear to the front of the truck bed. The truck bed may be enclosed with doors at the end of the truck body through which stacks of lumber may be loaded onto or unloaded from the conveyor rollers. A stack of lumber may be readily loaded onto or from the pallet rollers 16 by raising the pallet to the height of the conveyor rollers on the truck bed with the axes of the pallet rollers 16 being substantially parallel to the conveyor rollers. Then the load may be transferred with turning of the truck conveyor rollers (not shown) and the pallet rollers 16.

While only two rollers 16 are shown on the illustrated pallet 10, it is to be understood other load supporting rollers could be added to and journaled on the pallet frame to support the load at additional points or areas and to assist in the case of transfer of the load. Such additional rollers on the pallet could either be idler rollers which are not driven as by the drive system 40; or, on the other hand, the additional rollers on the pallet could be driven through gears or belts to turn with the illustrated rollers 16 at the ends of the pallet. In another embodiment of the invention (which is not shown) sockets are formed in the ends of the roller shafts and the illustrated square-end trunnions 42 projecting outwardly from the end plates 20 are eliminated. Instead, the projecting trunnions are on the wrench 44 for insertion into the sockets formed in the ends of the rollers 16 to turn the rollers and shift the load thereon. I

While one specific embodiment of the invention has been shown and described, it should be apparent that various modifications could be made therein without departing from the scope of the invention. For example, a pair of rollers could be located at each side of the pallet to transfer the load, especially-when the load is extremely heavy.

Various of the features of the invention are set forth in the following claims.

What is claimed is:

1. A pallet for receiving the forks of a lift truck in a given direction and for transferring the load from the pallet in a direction lateral to the given direction, said pallet comprising: a rectangular frame having a pair of parallel end members and having a pair of parallel side members joined at opposite ends thereof to said end members, said end members having spaced apertures therein to admit forks of a lift truck, a pair of elongated channels secured to said end members having internal openings aligned with said apertures for receiving said forks of said lift truck, a pair of rollers journaled centrally of the height of the end members for rotation about axes parallel to said side members for supporting the load, means enabling drive of said rollers for rotating the same to transfer the load in the lateral direction, a ratchet means associated with each of said rollers, a pawl means engageable with said ratchet means to hold said ratchet means against turning, a biasing means urging said pawl means in a direction parallel to said axes to engage said ratchet means and thereby hold said rollers against turning, and means enabling shifting of said pawl means against the urging of said biasing means and a turning thereof to an inoperative position to allow turning of said rollers by said means enabling driving of said rollers.

2. A pallet in accordance with claim 1 in which said ratchet means comprises a plurality of axially extending slots formed in the end of each roller.

3. A pallet in accordance with claim 1 in which said channels are enclosed by a pair of top and bottom walls joined to a pair of side walls to enclose said forks, and elongated stiffeners are secured to said end members having the fork receiving apertures therein to stiffen the same at said apertures.