Patent ID: 7717665
Filing Date: 2010-05-18
Classification: B65G

Abstract:
1. A pallet stacker for stacking loaded pallets one on top of the other, each pallet having a leading edge, a trailing edge, and opposing sides and being adapted to carry a load, said pallet stacker comprising: a stationary work station having first and second elongated support columns between which a first pallet having a first load may be located; a first pallet lift carriage in operational engagement with one of said first and second support columns and being selectively engageable with said first pallet on one of said pallet's opposing sides; a second pallet lift carriage in operational engagement with the other of said first and second support columns and being selectively engageable with said first pallet on the other of said pallet's opposing sides; each of said first and second lift carriages and, therefore, said first pallet when same is selectively engaged therewith, being vertically adjustable within said work station, whereby a second pallet having a second load may be located within said work station beneath said first pallet to receive said first loaded pallet in stacked relation upon said second loaded pallet; a drive system having an output in operational engagement with said first and second pallet lift carriages for driving vertical adjustment of said first and second pallet lift carriages; a first drive chain having a first end and a second end, said first drive chain being in operational engagement with said output of said drive system and having said first end of the first drive chain fixed relative to said first pallet lift carriage; a second drive chain having a first end and a second end, said second drive chain being in operational engagement with said output of said drive system and having said first end of the second drive chain fixed relative to said second pallet lift carriage; and a spring-loaded chain tension mechanism associated with at least one of said second ends of said first and second drive chains, said chain tension mechanism being operable to change its configuration so as to allow said at least one second end of said first and second drive chains to float relative to a respective one of said first and second pallet lift carriages to thereby allow for vertical adjustment of one of said first and second pallet lift assemblies relative to the other.