Turning – Process of turning
Patent
1997-04-11
1999-09-28
Pitts, Andrea L.
Turning
Process of turning
409141, B23B 300
Patent
active
059570164
ABSTRACT:
Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.
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Redmond James M.
Segalman Daniel J.
Abeyta Andrew
Bhargava Adesh
Grafe V. Gerald
Pitts Andrea L.
Sandia Corporation
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