Design optimization of tool extension components in machine tool assemblies based on the absorber effect between subcomponent modes

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2022-9

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Tola, Hatice Elif

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Regenerative vibrations, called chatter, are a major problem limits productivity due to poor surface finish, low material removal rates and decrease in life of machine tool and equipment. Stability lobe diagrams are graphs that give a stable cutting limit at a given spindle speed, developed by the researchers as a chatter prevention tool. Various methods have been investigated to increase the critical cutting limit and suppress the most flexible mode in the machine tool frequency response function(FRF). Tuned mass dampers(TMD) are one of the most widely used tools which achieve vibration attenuation by matching its natural frequency with the system’s. This absorber effect can also be obtained by macthing the modes of the subcomponents of the machine center. A new component can be introduced to the system when modification of the subcomponents such as holder and tool is inconvenient. In this thesis, optimal designs for tool extension component aiming absorber effect is investigated. Dynamic properties of the spindle-holder assembly are acquired by impact hammer tests. Spindle is identified by FRF de-coupling method based on the experimental FRF data of spindle-holder assembly. After FRFs of each subcomponent is obtained, optimal design parameters of the extension and tuning of the extension-tool assembly is investigated to have absorber effect by simulations.

Subject Keywords

Chatter Stability, Machine Tool Dynamics, Spindle Identification, Design Optimization

URI

https://hdl.handle.net/11511/99712

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

H. E. Tola, “Design optimization of tool extension components in machine tool assemblies based on the absorber effect between subcomponent modes,” M.S. - Master of Science, Middle East Technical University, 2022.