Material handling apparatus

Claim 1

A material-handling vehicle, comprising, in combination: a base frame; a mast assembly mounted on said base frame; a first carriage suspended from and guided for vertical movement by said mast assembly, said first carriage having four rollers journalled therein for rotation about horizontal longitudinally-extending axes and spaced in a row across the front side of said first carriage; an intermediate carriage mounted on said first carriage for lateral movement relative to said first carriage, said intermediate carriage including first and second channel recesses extending across the rear and front sides, respectively, of said intermediate carriage, and a pair of gear racks affixed to and extending across the front side of said intermediate carriage adjacent the upper and lower edges thereof, said four rollers being seated in said first recess on the rear side of said intermediate carriage; a traverse carriage mounted on said intermediate carriage for lateral movement relative to said intermediate carriage, said traverse carriage including a vertically-extending rigid member which extends to a level below the lower one of said gear racks, a further roller journalled on said vertically-extending rigid member for rotation about a longitudinal axis, said further roller being seated within said second recess on the front side of said intermediate carriage to transmit vertical force from said rigid member to said intermediate carriage; a pair of arms extending longitudinally forward in a fixed direction from said rigid member; a loadengaging carriage support between said arms for pivotal movement at least 90° in either direction from said fixed direction about a vertical axis adjacent the forward ends of said arms; a vertically-extending shaft means journalled on said rigid member; a pair of gears affixed to said shaft means, each of said gears engaging a respective one of said gear racks on said intermediate carriage, and first motive means mounted on said vertically-extending rigid member and connected to rotate said shaft means, thereby to move said traverse carriage laterally relative to said first carriage means, a first and a second of said four rollers on said first carriage are journalled on said first carriage adjacent the lateral edges thereof, respectively and the third and fourth rollers are spaced in between said first and second rollers, said third roller being closer to said first roller than to said fourth roller and said fourth roller being closer to said second roller than to said third roller, said shaft means comprises a hollow shaft carrying said gears, a fixed shaft extending through said hollow shaft and affixed to said rigid member, and bearing means for rotatably supporting said hollow shaft on said fixed shaft.