Tasuku Osada

Monitoring of Lapping Process by Audible Sound.

In this paper, using audible sound caused by the vibration of the work and weight, monitoring methods during the lapping process are discussed. And with a microphone, a non-contact process monitoring method is established. The authors had already confirmed that it is possible to predict the roughness of the processed surface by detecting the vibration acceleration signals of the revolving work. Considering that experienced workers can judge processing conditions by their sense of hearing, it is possible to monitor the process by audible sound.But the necessary useful signals cannot be obtained by just putting a microphone close to the work. So for the purpose of picking up the signal easily, two methods are proposed. They are (1) making the weight into exponential horn shape to amplify the vibration, and (2) drilling holes in the weight and making use of the resonance of the air in the holes. According to the results of the experiment, it is confirmed that if the resonance frequencies of the horn and the air column in the holes are appropriately selected, process surface condition can be monitored by either methods mentioned above.