抄録
Small fishing boats meet marine peril associated with engine damage on account of insufficient maintenance and aggressive operation in Japan. The failure diagnosis on reciprocal engine is more difficult than independent mechanical elements, because almost reciprocal engine is composed of great number of structural bodies and mechanical elements. Reciprocal engine find it hard to identify of failure elements to exist a number of noise sources within the engine. This paper experimentally examines the possibility of diagnose abnormal conditions about a four stroke twin cylinder reciprocal engine from generated vibration signals measured by accelerometers. Artificially assumed abnormal conditions in the reciprocal glow engine are concerning push rod driven rocker arm. Identification of above abnormal conditions has been carried out based on AR model constructed by normal vibration signal associated rotational frequency of the reciprocal glow engine. In conclusion, it is possible to diagnose above abnormal conditions even though differing degree of accuracy.
