Patent ID: 7161114
Filing Date: 2007-01-09
Classification: B23K

Abstract:
1. A machine tool installation for laser cutting of sheet metal workpieces comprising: (a) a workpiece support having a multiplicity of parallel spaced grid elements providing the upper surface thereof; (b) a machine frame having a generally vertical rear wall and an arm extending therefrom over said workpiece support, said grid elements of said workpiece support extending perpendicularly to said vertical wall of said machine frame, said vertical rear wall having a recess therein opening adjacent said workpiece support; (c) a laser cutting unit supported on said arm of said machine frame and including a laser cutting head, said cutting head being movable in X and Y axes over said workpiece support to cut parts from a sheet metal workpiece disposed thereon; (d) an unloading unit for lifting the cut parts from said workpiece support and transporting them to a discharge station, said unloading unit having (i) a frame movably supporting (ii) a pair of opposed fork assemblies, (iii) a fork housing supporting said frame and enclosing (iv) a drive assembly for moving said fork assemblies between open and closed positions, said fork assemblies being spaced apart in the open position and having their opposed ends in adjacent relationship in the closed position, one of said fork assemblies being movable into said frame recess in said open position, said fork assemblies in said closed position being movable vertically between said grid elements of said support to lift the parts from said grid elements, said unloading unit also having (iv) a support housing on which said fork housing is mounted for vertical movement, and (v) drive means for effecting vertical movement of said fork housing relative to said machine frame and said workpiece support, said unloading unit being movable on said machine frame between an operative position adjacent said workpiece support and the discharge station; (e) drive means for moving said unloading unit between the operative position and discharge station; and (f) a controller operable to (i) move said unloading unit between said discharge station and said operative position, (ii) move said fork assemblies into the open position, move said fork housing downwardly to position the fingers for movement into the spacing between said grid elements, (iii) move said fork assemblies into the closed position below the upper surface of said workpiece support, (iv) move said unloading unit upwardly to lift the cut parts and skeleton from said workpiece support, and (v) discharge the parts and skeleton on said unloading unit at the discharge station.