US Patent 7404347 Noncircular working device

A working device of a noncircular workpiece, such as a piston of an internal combustion engine, is improved. A workpiece 10 is held by a work spindle and rotated. A noncircular working device 100 has a noncircular working unit base 110 and is provided with a servo motor 104. A noncircular working unit 120 is positioned along a Y axis, and an arbitrary cutting tool 133 is selected from a cutting tool group 130. A servo motor 112 reciprocates the noncircular working unit 120 on an X2 axis in synchronization with the rotation of the work spindle and performs noncircular working of the workpiece 10.