Influence of the excitation force amplitude on vibration characteristics of a linear rolling bearing

In machining processes of machine tools, guideways are subjected to the various dynamic force and moment. This paper describes the influence of the force amplitude on the dynamic characteristic of a linear rolling bearing. The carriage is excited in the feed and lateral direction respectively. The excitation force and the response acceleration of the carriage are detected respectively with a force transducer and an accelerometer. The frequency response function (FRF) is calculated based on the detected signals. To investigate the influence of the force amplitude, the FRF is measured with various force amplitude. As the result, the dynamic characteristic of a linear rolling bearing is varied with the force amplitude only when the carriage is excited in the feed direction. The frequencies and damping ratios of resonance peaks which are observed on the FRF decrease when the force amplitude increases. Then the relationship between the friction force and displacement is measured for clarifying the force amplitude dependence of the dynamic characteristic of linear rolling bearing. From the relationship between the friction force and displacement, the force amplitude dependence of the dynamic characteristic of linear rolling bearing will be due to the friction force in the pre-rollìng region.