Micro crane finishing line system

A material finishing line including a essentially linear array of work stations is disclosed. A stationary support beam extends over the work stations and substatially encloses a transmission, and supports at least one crane body and a drive means to selectively propel the crane body along the support beam. The crane body is an assembly of components arranged to raise workpieces from the work stations towards the support beam. A 'U' shaped cart supports lift means to provide power to raise a lift arm and supports the lift arm and a lift arm guide. The vertical extensions of the support beam and of the cart are reduced and nearly overlap, and the vertical extension of the lift arm may be lifted into substantially overlapping relationship with the vertical extension of the cart. The ability to substantially tuck the lift arm onto the cart and a reduced vertical extension of the cart and support beam provide a material finishing line which only requires minimal headroom while reducing the dead space through which a workpiece cannot be lifted. To the same end, transmission means to propel the cart and conductors to supply the mobile lift means are substantially contained within the support beam and cart. Additionally the support beam is an assembly of support modules, which in turn are assemblies of easily fabricated standard shapes. Similarly the crane body components are assembled from easily fabricated standard shapes.