Apparatus for machining a non-circular workpiece

An apparatus for machining a non-circular workpiece wherein a spindle to which a workpiece is attached is rotated while a tool is moved back and forth in a direction perpendicular to the axis of said spindle to machine the workpiece so as to have a desired non-circular sectional shape, comprising:

• a tool mount member disposed for movement in a direction perpendicular to the axis of said spindle;
• a tool support means for supporting said tool on said tool mount member for reciprocating movement in the same moving direction as that of said tool mount member;
• a high speed actuator placed on said tool mount member for moving said tool back and forth at a high speed with respect to said tool mount member;
• a motor for moving said tool mount member back and forth in the direction perpendicular to the axis of said spindle;
• a profile data storage means for storing therein profile data which are calculated from said desired non-circular sectional shape and define a position of said tool in a direction perpendicular to the axis of said spindle with respect to an angle of rotation of said spindle;
• a profile data separating means for separating said profile data into low frequency components and high frequency components;
• a first control means for actuating said motor, in a synchronized relationship with the rotation of said spindle, in accordance with data indicating said low frequency components of said profile data separated by said profile data separating means so that said tool mount member is moved to produce a first movement corresponding to said low frequency components of said profile data;
• and
• a second control means for actuating said high speed actuator, in a synchronized relationship with the rotation of said spindle, in accordance with data indicating said high frequency components of said profile data separated by said profile data separating means so that said tool is moved relative to said tool mount member to produce a second movement corresponding to said high frequency components of said profile data, said tool being moved by a composite movement composed of said first movement of said tool mount member and said second movement of said tool relative to said tool mount member to produce a movement corresponding to said profile data.