A FAST ON LINE QUALITY CONTROL OF REFRIGERATORS BASED ON THERMAL IMAGE DETECTION AND POWER CONSUMPTION

摘要

At the end of the production process of a refrigerator, it is necessary to verify if the refrigerator works correctly by detecting possible manufacturing and assembling defects. Up to now, on-line quality control is based mainly on the measurement of temperatures taken inside a refrigerator that works for 30-90 minutes. This leads to a very high consumption of energy to cool the refrigerators and of space to store the refrigerators during the testing period. The aim of this paper is to design an automatic on line system, based on thermal imaging of the condenser and the compressor, for detection of faulty refrigerators. With the thermal image approach it is possible to reduce the on line test time below 8 minutes, assuring even a higher level of accuracy in the diagnosis of defected refrigerator. This is an effective and non contact method that provides a quick thermal evaluation feasible for a 100% on line quality control of refrigerator. Moreover using appropriate Signal Process Techniques, the collected data are analyzed and the classification, i.e. refrigerator good and faulty, is automatically performed without any operator.