Abstract:
A pallet truck adapter having side by side shoes for fitting over pallet supporting tines, in which the shoes are of different heights. This facilitates locating one pallet on the higher shoe, lifting it slightly off of the supporting surface, and then moving to and lifting another pallet on the lower shoe. The adjacent pallets can then be moved together and off loaded at different locations, unloading the pallet on the lower shoe first, and the pallet on the higher shoe thereafter.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of U.S. application Ser. No. 13/365,743 filed Feb. 3, 2012. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     REFERENCE TO SEQUENCE LISTING, A TABLE OR COMPUTER PROGRAM LISTING, COMPACT DISK APPENDIX 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to pallet truck adapters and, more particularly, to a method for moving pallets from place to place on a pallet truck. 
     2. Background Art 
     Pallet truck adapters are typically mounted on the tines of a fork lift truck, walkie rider or pallet jack, in order to more specifically adapt the truck to particular uses. The term “pallet truck” as used herein refers to any mobile device designed to carry pallets on tines which can be inserted beneath the pallet and raised to lift the pallet for carrying and lowered to place the pallet at a desired location. Thus, “pallet truck” encompasses a fork lift truck, a so called walkie rider, a pallet jack, or like device. Such trucks typically have a pair of tines, though sometimes more, which are inserted under a pallet. However, the term “tine” is intended to include a single pallet lifting platform, or several tines, serving the same lifting, carrying and lowering function of the more typical pair of tines. Likewise, the tines of a walkie rider or pallet jack are often thicker than those of a fork lift truck, and often include floor engaging wheels located in the tines, which are associated with a lifting mechanism located in the tines, such that as the tines are elevated, the wheels continue to make contact with the floor. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention, a method is provided for moving pallets from place to place on a pallet truck. The pallets are sufficiently small in width so that two can be moved on a set of pallet truck tines. The method includes providing a pallet truck adapter having at least a pair of shoes for fitting over pallet supporting tines. The shoes have bottoms, tops, and sides. The shoe bottoms are both in approximately the same plane, and the shoes are of differing heights. The method in accordance with the invention comprises manipulating the pallet truck so as to locate the taller shoe beneath a first pallet resting on the floor. The pallet adapter is then lifted slightly off of the supporting surface by raising the pallet truck tines. The first pallet is then moved, and the lower shoe of the adapter is located beneath a second pallet resting on the floor. The adapter is further raised to also lift the second pallet off the floor. Both the first and second pallets are thus moved about, and are deposited in the same location, or alternatively, in separate locations, by lowering the adapter such that the second pallet makes contact with the supporting floor first, and then the first pallet makes contact with the supporting surface. 
     These and other objects, advantages and features of the present invention will be more fully understood and appreciated by reference to the specification and appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a slightly elevated perspective view of the pallet truck adapter of the preferred embodiment; 
         FIG. 2  is a bottom plan view of the adapter; 
         FIG. 3  is a rear elevation of the adapter 
         FIG. 4  is a cross sectional view of the adapter taken along plane IV-IV of  FIG. 1 , with the support legs in their elevated position; 
         FIG. 5  is the same cross sectional view with the legs in their lowered position; 
         FIG. 6  is an exploded view of the leg assembly, showing the leg in its elevated position; 
         FIG. 7  is an enlarged cross sectioned perspective view of a portion of the adapter, showing the manner in which the detent pin helps hold the leg in its elevated position. 
         FIG. 8  is the same view as  FIG. 7 , showing the manner in which the detent pin helps hold the leg in its lowered position. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the preferred embodiment, pallet truck adapter  1  comprises a right shoe  10   a  and a left shoe  10   b  for fitting over the tines of a pallet truck, joined by a backstop plate  2  and a bottom brace  3 . ( FIGS. 1-3 ) Backstop plate includes spaced openings  2   a  one of which is aligned with the interior of right shoe  10   a  and the other of which is aligned with the interior of left shoe  10   b . This allows the tines of a fork lift truck to be inserted into shoes  10   a  and  10   b , so that adapter  1  can be raised and lowered with the tines of the fork lift truck. 
     Each shoe  10   a - b  includes a retractable leg assembly  20 . Legs  21  of each assembly can be retracted as shown in  FIGS. 4 and 6 , or lowered as shown in  FIGS. 1, 3 and 5 , by pulling or pushing, respectively, an actuator rod  30 . Legs  21  are sufficiently long that, when lowered, they leave a gap between the bottom of shoes  10   a  and  10   b  and the floor on which adapter  1  is resting. This gap is tall enough that the tines of a walkie rider, pallet jack or like device having tines with floor engaging wheels can slide underneath adapter  1 , to facilitate adapter  1  being raised and lowered with the walkie rider tines. 
     Once the tines of a fork lift or walkie rider are inserted fully into or beneath, respectively, shoes  10   a  and  10   b , chain and quick-disconnect clip  4  can be used to secure adapter  1  to the fork lift truck or walkie rider. Preferably clip  4  is a carabiner clip. If the legs  21  had been in their lowered position, they can be raised. 
     Preferably, each shoe  10   a  and  10   b  is sufficiently wide to stably support a half size pallet, with legs depending downwardly on opposite sides of the shoe. The shoes are sufficiently short from top to bottom that the legs of the pallet extend below the bottom of the shoes. Thus, a forklift truck or walkie rider with adapter  1  attached can be driven into position with the one or both of the shoes of adapter  1  passing beneath a pallet or pair of side by side pallets, each shoe passing between the legs of a pallet. When the tines are raised, adapter  1  and pallets supported thereon are raised accordingly. When the tines are lowered, adapter  1  is lowered, and the pallet legs come to rest on the floor at the location desired for their placement. The walkie rider or forklift truck can then be operated in reverse, so that shoes  10   a  and  10   b  slide out from under the pallet or pallets. 
     The sidewalls of right shoe  10   a  are taller than the sidewalls  12  of left shoe  10   b . Shoes  10   a  and  10   b  are arranged with their bottoms aligned. In this way, right shoe  10   a  can be used to pick up or drop off a pallet in a different location than left shoe  10   b . Thus for pickup, right shoe  10   a  can be slid into position below a first pallet, raised slightly to lift the first pallet off of the floor, and the truck or walkie rider moved to a different location for picking up another pallet using left shoe  10   b . Because it is shorter in height, left shoe  10   b  can be slid under a second pallet while the first pallet is held slightly elevated off of the floor. The tines of the forklift truck or walkie rider can then be elevated still farther until both the first and second pallets are lifted off of the floor. The pallets can then be moved to a different location and the tines, and accordingly shoes  10   a  and  10   b , lowered sufficiently that the pallet being carried by the shorter shoe  10   b  engages the floor. Shoe  10   b  can be slid out from beneath the pallet which is now supported by the floor, leaving it in place. The truck or walkie rider is then moved to a different location where its tines are lowered still farther so that the first pallet supported by the taller shoe  10   a  engages the floor. Shoe  10   a  can then be removed from beneath the pallet so lowered to the floor. If adapter  1  is no longer needed on the times, it can be driven to a storage location, legs  21  rotated downwardly into their erected position by pulling on actuator rod  30 , and adapter  1  lowered to the floor by lowering the tines. Once it is resting on the floor, the forklift or walkie rider can be operated in reverse to remove the tines from within or from beneath adapter  1 , respectively. 
     Adapter  1  is preferably made of steel or other rugged material. Each shoe  10   a  and  10   b  is box-like in configuration, having a top wall  11 , downwardly depending sidewalls  12  and a generally open bottom. Bottom braces  13  which are “L” shaped in cross section extend across the open bottom of each shoe  10   a  and  10   b , between the opposite sidewalls  12 . Two cross braces  13  are located towards the front of each shoe. A third cross brace  13  is positioned generally midway between the front of the shoe and its junction with back plate  2 . The fourth brace  13  is positioned adjacent backstop plate  2 , and the vertical leg of the fourth brace is secured to backstop plate  2 . 
     Elongated load support strips  14  are located on shoe top plate, near each of the opposed side edges thereof. A pallet being supported by shoe  10   a  or  10   b  will rest on load support strips  14 . Each shoe  10   a - b  has a side wall  12  facing inwardly towards the inwardly facing side wall  12  of the other shoe, and an outwardly facing sidewall  12  which faces away from the adjacent shoe. Located at the bottom of each shoe  10   a - b , and towards the outwardly facing sidewall  12  of each shoe  10   a - b  is a bottom guide rail  15 , also referred to herein as a walkie tine guide rail  15 . Each guide rail  15  is generally “L” shaped in cross section so that it has a downwardly extending leg. The tines of a walkie rider can slide between guide rails  15 . Each guide rail  15  on each shoe  10   a  and  10   b  is bolted to the front, middle and back bottom braces  13 . As shown in  FIG. 2 , guide rails  15  are spaced at their maximum distance apart. Alternative bolt holes  13   a  are provided on the front, middle and back bottom braces  13  so that guide rails  15  can be moved closer towards one another, thereby providing for a reasonably close fit at the outside edges of walkie rider tines, no matter what the combined width of the walkie rider tines is. 
     Located in the interior of each shoe  10   a  and  10   b  are spaced inner and outer interior guide rails  16  and  17  ( FIGS. 1, 2 ), sometimes referred to herein as forklift tine guide rails  16  and  17 . These guide rails are “L” shaped in cross section. Each outside rail  17  is the taller of the two, and is adjustably secured to the underside of shoe top wall  11 . Guide rail  17  serves not only as a guide rail for the forklift tines which are inserted through openings  2   a  in the backstop wall  2 , but also serves to protect the retractable leg assembly  20  from being hit by the forklift tines as they are inserted into the shoes  10   a  and  10   b . The inner forklift tine guide rails  16  are mounted on mounting bars  16   a , which in turn are secured to the underside of shoe top wall  11 . Outer guide rail  17  can be adjusted to one of several different positions, in order to accommodate forklift tines of differing widths between outer interior guide rail  17  and inner interior guide rail  16 . 
     The retractable leg assembly  20  comprises legs  21  pivotably mounted between outer and inner mounting plates  22  and  23 , respectively, and joined at their tops by an elongated actuator rod  30  ( FIGS. 4-6 ). The outside mounting plate  22  is secured to the outwardly facing shoe wall  12  by fasteners  22   a ,  22   b  and  22   c  ( FIGS. 1, 7 and 8 ). Each leg  21  and a leg stop block  24  are positioned between outer mounting plate  22  and inner mounting plate  23 . Leg stop block  24  includes a raised leg stop surface  24   a , and a lowered leg stop surface  24   b . These surfaces limit the position of the legs  21  in their raised and lowered positions respectively. 
     Locator pins  25  pass through mating holes in inner mounting plate  23 , leg stop block  24  and outer mounting plate  22  ( FIG. 6 ). Rear mounting bolts  26  pass through apertures at the rear of inner mounting plate  23 , the rear of leg stop block  24  and are threaded into receiving apertures in outer mounting plate  22 . Forward mounting bolt and pivot axle  27  passes through a forward aperture in inner mounting plate  23 , passes through a bushing  28  which itself is located in a pivot aperture  21   a  located about two-thirds up the length of leg  21 . Bolt  27  then threads into a forwardly and centrally located threaded aperture in outer mounting plate  22 . 
     An elongated control rod  30  and a stabilizer bar  31  are connected to the upper ends of each pair of front and rear legs  21 . Control rod connector bolts  31   a  pass through apertures in stabilizer bar  31 , and through bushings  31   b  which are positioned in leg aperture  21   b  near the upper ends of legs  21 . Bolts  31   a  are then threaded into receiving apertures in control rod  30 . A control rod actuator knob  32  is threaded onto a threaded member  33  which in turn threads into a nut  34  which is welded or otherwise secured to the end of control rod  30 . Control knob  32  is located at or near the front opening in shoe  10   a - b , so as to be readily manipulated. By pulling on control knob  32 , one pulls on control rod  30 , causing legs  21  to rotate downwardly until they hit leg stop surface  24   b . Similarly, legs  21  can be raised (retracted) by pushing against knob  32  and rod  30  to rotate legs  21  upwardly until they engage leg stop surface  24   a.    
     A detent member  29  is provided to engage at least one of the legs  21  to hold it in its retracted or extended position. Detent  29  is a threaded member having an internal spring loaded plunger. It is threaded into a nut  29   a  which is welded or otherwise secured to inner mounting plate  23  until the tip of detent  29  engages leg  21  with the desired force. 
       FIG. 7  is a partially cross sectioned view which shows the relative positions of the control rod  30  and leg  21  in the legs retracted position.  FIG. 8  is the same cross sectional view, but showing the relationship between the components when leg  21  is in its lowered (extended) position. 
     In operation, pallet truck adapter  1  will be stored in some location, preferably with legs  21  extended. Legs  21  don&#39;t have to be extended if adapter  1  is going to be used with a forklift truck rather than a walkie rider. Indeed, leg assemblies  20  can be omitted entirely if the adapter is to be used solely with a fork lift truck. However with legs  21  in their extended, erect position, adapter  1  can be loaded onto the tines either of a forklift truck, which are inserted through openings  2 A in backstop plate  2  and on into the interior of shoes  10 A and  10 B, between forklift tine rails  16  and  17 ; or alternatively, the tines of a walkie rider can be slid underneath adapter  1  with its legs  21  extended, and with the walkie rider tines positioned between the walkie tine guide rails  15 . The position of guide rails  15  can be adjusted to accommodate wider or narrower walkie rider tines. Similarly, the adjustable outer forklift tine rails  17  can be adjusted to different positions to accommodate forklift tines of differing widths. 
     With the forklift or walkie rider tines in position, adapter  1  can be quickly secured to the truck or walkie rider using the quick disconnect clip  4 . The tines are then raised to lift adapter  1  off of the floor, control knob  32  is pushed to cause legs  21  to retract into their upper position, and adapter  1  is now ready for use in conjunction with the walkie rider or forklift truck. 
     The truck or walkie rider is conveyed to the location of a “half pallet,” and taller shoe  10   a  is inserted between the legs and beneath the bottom surface of the pallet. The pallet can then be raised slightly by raising the tines and the adapter  1 , moved to another location and the shorter shoe  10   b  can then be inserted between the legs and below another half pallet. By raising the tines still further, the second pallet is also lifted off of the floor. The process can then be reversed to deposit the two pallets in the same or different destination positions. 
     Upon completion of use, the adapter can be stored by pulling on control knob  32  and control rod  30  to again extend the legs. The tines are lowered until the adapter  1  is resting on the floor, and the tines can then be removed by reversing the walkie rider or forklift truck. 
     Of course it is understood that the foregoing is a preferred embodiment of the invention and that various changes and alterations can be made without departing from the spirit and broader aspects of the invention.