Patent ID: 7328638

Claim:
An apparatus for machining a cylindrical work piece, comprising: a substantially cylindrical work piece mounted for rotational movement; a drive unit connected to the work piece for rotating the work piece; a tool post mounted on a track for movement substantially parallel to a surface of the work piece to be machined; an actuator mounted on the tool post, the actuator comprising: a main body having an aperture; a piezoelectric stack secured and preloaded in the main body aperture; a tool tip carrier connected to the piezoelectric stack; and a tool tip mounted on the tool tip carrier, wherein the piezoeloctric stack moves the tool tip in an x-direction substantially perpendicular to a surface of the work piece to be machined; and a controller, connected to the drive unit and the actuator, for controlling the movement of the work piece relative to the tool tip via the drive unit and for controlling the movement of the tool tip via the piezoelectric stack, wherein the controller via the piezoelectric stack moves the tool tip into and out of the surface of the work piece to be machined during cutting of the surface in order to make discontinuous features in the surface of the work piece.