THEORETICAL RESEARCH CONCERNING THE INFLUENCE OF VIBRATIONS UPON THE MILLING ACCURACY

Mihai Ispas
Prof.dr.ing. - Universitatea "Transilvania" din Brasov - Facultatea de Industria Lemnului
Address: B-dul. Eroilor, nr. 29, 500036 Brasov, Romania
Tel./Fax.: 0040 268 419581. E-mail: ispas.m@unitbv.ro

Abstract: The objective of this paper is an estimation of the influence of vibrations upon the quality of milled surfaces. The method used is based on a computer simulation of the trajectories described by the cutting edges of the tool. The calculus of their consecutive coordinates was performed by considering several situations characterised by the absence and then the presence of harmonic vibrations. The obtained results showed that the vibrations with much lower frequency than the rotation frequency of the main shaft have the most unfavourable influence upon the quality of the processed surfaces, followed up by the imbalance vibrations (with an equal frequency with the frequency of the main shaft), and finally by those generated by the cutting force per tooth.

Key words: rotary milling, surface quality, vibrations, computational simulation.

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