Quantitative Measurement Method of Contact Stiffness of the Joint with Different Material Combination

Abstract

The joints in machine tools influence greatly the static, dynamic and thermal characteristics of the machines. Then the many researches on them have been carried out. Under these conditions, the authors have established the quantitative measurement method of contact stiffness of the joint with same material combination considering the real contact area, since the real contact area is far smaller than the nominal contact area. In this research, we propose the new measurement method of contact stiffness of the joint with different material combination expanding the former method we developed and its validity is considered. In consequence, the following results are obtained. 1) The measurement method applicable to the joint with various material combinations is established using inserted specimens. 2) The real contact area of the joint with different material combination can be accurately measured considering the reflected level of ultrasonic wave at the real contact area of the joint. 3) The contact stiffness of the joint with different material combination can be treated as the series coupling of the each contact stiffness constructing the joint. 4) The contact stiffness of the joint and each contact stiffness of the contact springs constructing the joint can be measured by the proposed method.