PURPOSE: To improve productivity and machining accuracy in the grinding of a long-sized workpiece such as a spindle.
CONSTITUTION: A complex machine tool is provided with a first spindle 35 and a second spindle 55 disposed opposedly on a table, and the second spindle 55 is movable toward the first spindle 35. The first spindle 35 is provided with a sliding center 410 which can be pulled into the spindle 35, and a collet attachment 360 for holding the sliding center 410. A turning mill unit and a grinding unit provided with linear moving shafts orthogonal to the axes of the first and second spindles are disposed to center-support a workpiece 45 in a first chucking process so as to turn/grind its outer peripheral surface 451. In a second chucking process of pushing the workpiece 45 into the first spindle 35 to hold it directly by the collet attachment 360, the flange and tapered hole of a spindle are turned and ground.
YOSHIDA HISASHI
IWATA KEIICHI
