Host: The Japan Society of Mechanical Engineers
Name : Mechanical Engineering Congress,Japan
Date : September 11, 2016 - September 14, 2016
Reaming is a finishing process to be performed in order to improve the accuracy of the prepared hole drilled. In this process, a chatter vibration often occurs and the drilled hole is deformed in a polygonal shape. This polygonal deformation phenomenon becomes a problem, because of decrease in the precision of the hole. A countermeasure by irregular tooth spacing is proposed and the prevention effect is confirmed. But, the mechanism has not been clarified yet. The generating mechanism of the polygonal deformation is considered to be a self-excited vibration caused by time delay. In this paper, an analytical model for the case of tool rotation is proposed. Also, the natural frequency and the stability of the self-excited vibration is analyzed numerically in both cases of equal spacing and unequal spacing of the teeth. The numerical result agrees well with the actual phenomenon qualitatively.
