Vibration Resistance at Processing by End Mills With Variable Pitch

Abstract

In this work there is carried out an investigation
 of tooth different pitches with the purpose to increase a
 technological system vibration resistance at processing
 by end mills with a variable pitch and using elements
 of an operation modal analysis (OMA).
 An experiment is carried out in the course of
 which there are performed tests for the level definition
 of vibrations and resonance frequencies of technological
 system oscillations at cutting by an end mill with a
 constant and varied pitch. The work results show that
 the average level of vibrations at the work with a mill
 with a constant pitch is higher than at the work with a
 mill with a varied one. The existence of some own frequencies
 in one direction for a mill with a constant
 pitch of teeth is defined that is possible in the systems
 with a great number of degrees of mobility. At the
 same time for a mill with a varied pitch the oscillations
 were observed only at one frequency of own oscillations
 in one direction. In this connection a possibility
 of resonance oscillations decreases. During the work of
 the mill with a varied pitch the vibration waves with
 different length appear on the surfaces of cutting. A
 developed physical model of a technological system
 oscillation process at the work with a mill with a varied
 pitch shows that with the increase of a circular pitch
 the resultant oscillation displacements decrease.