A method for machining of workpieces (do with rotating cutting tools and spindle mechanism for machine tools for carrying out this method

摘要

A dual spindle assembly is provided which has a hollow outer member having an inner member rotatably and eccentrically mounted therein. The inner spindle member has a mounting hole defined eccentrically in one end for engaging a cutting tool. In order to make possible a continuous change in the radius of revolution of the cutting tool about the axis of the outer spindle member, a plurality of worms extend parallel to the spindle assembly and are geared to one another for joint rotation. Ball nuts on the worms travel back and forth along the same with the bidirectional rotation thereof. Rigidly interconnecting the ball nuts, a connector surrounds the spindle assembly via a ring rotatably mounted therein. The ring has an inward projection making threaded engagement with the inner spindle member through a slot cut longitudinally in the outer spindle member. The linear travel of the ring with the ball nuts results in the rotation of the inner spindle member relative to the outer. The inventive method calls for the use of a multitip cutting tool having two or more tips of different characters disposed at equal distances from its axis of rotation. The spindle assemby makes it possible to use any one of the tool tips for boring or like operation with a desired cutting radius as the tool is mounted thereto in a prescribed angular position with respect to the outer and inner spindle members.