| Summary: | In recent years, the rapid progress in the field of maohine tools has necessitated a more accurate determination of the cutting forces for design purposes than has been possible in the past. In the milling operation, the chip section changes along the cut and this change causes a fluctuation of the cutting force. The designer of milling machines must know the maximum force values and the amplitudes of the force pulsations, whilst the user must be able to select cutting conditions which will keep the pulsations within permissible limits. The investigation was started by improving a Three-Component Milling Dynamometer, details of which have already been published. The modifications aimed at a high natural frequency and greater measuring sensitivity. They were: (1) Increased stiffness of the measuring rings (2) Reduced weight of the top plate (3) Modifications of the electrical circuit The dynamoneter was capable of measuring from 1.5 to 1500 lb. and had a natural frequency of 720 cycles per sec. in its weakest direction and could thus be used up to 180 cycles per second, without the dynamic magnifier exceeding about 5%. The investigation into the chip section and cutting forces covered both slab and face milling.
|
|---|
