Transfer machine

Claim 1

A transfer machine, comprising: a movable indexing table having a plurality of workpiece positions where respective workpieces are positioned in use; a plurality of working units each defining a working station positioned around said movable indexing table opposite a respective workpiece position; means for moving said indexing table to change the respective workpiece position which is opposite a particular working unit; wherein each of said working units comprises a tool, infeeding means for infeeding said tool toward a respective workpiece position for working on the workpiece and for withdrawing the tool from the workpiece, a slide for displacing said tool along a direction perpendicular to the infeed direction, a screw-feed mechanism for moving said tool along said slide, driving means for driving said screw-feed mechanism to move said tool along said slide, an origin detector for defining a position origin along said slide and for detecting when said tool is at said origin, a tool position detector for detecting the amount of displacement of said tool away from said origin; and a numerical control system comprising means operable for actuating said driving means for driving said screw-feed mechanism, setting circuit means cooperative with said origin and position detectors for setting the displacement of said tool along said slide from said origin, and selecting circuit means for successively selecting successive working units for successively actuating their respective driving means and for successively setting the displacement of their respective tools along their respective slides independently of the operation of said infeeding means.