Warehouse shelving system

Claim 1

A shelving system for the storage of pallet-size loads, comprising: a plurality of stacks of shelves each vertically subdivided into a multiplicity of tiers positioned on the same levels in said plurality of stacks, longitudinally adjoining stacks being separated by a transversely extending aisle, each stack having a depth of several storage spaces each accommodating a pallet-size load, said aisle having a depth substantially equaling at least twice the depth of a storage space; hoisting means in said aisle including a pallet carrier alignable with the tiers of the adjoining stack on any level, said carrier comprising a platform, a longitudinally extendable arm on said platform substantially spanning the depth of said aisle when in a contracted position, lifting means alongside said arm on said platform, and transfer means mounted on said lifting means and longitudinally displaceable thereon between opposite extremities of said arm, the length of said transfer means being less than the length of said arm in said contracted position thereof; and mechanism on said carrier for placing said transfer means under a pallet riding on one extremity of the contracted arm, actuating said lifting means to engage said transfer means with the pallet and raise the latter off said arm, displacing said transfer means on said lifting means into an alternate position relative to said arm, depositing the pallet on the other extremity of said arm with disengagement of said transfer means therefrom, and extending said arm into the adjoining stack on the side of said other extremity, said stacks being provided at certain levels with throughgoing transverse passageways adjoining a single row of storage spaces next to said aixle.