Research On Optimizing The Automatic Inspection System Of Piston Rings

Piston ring is one of the most important components of internal combustionengine. The width of end gap and the degree of light leakage are significantparameters of piston ring that must be controlled in a certain range. The traditionalmanual detection method is inefficient and can’t meet the needs. It has seriouslyhindered the development of internal combustion engine.State Key Laboratory in Tianjin University is professional in laser/CCDdetection, they have made correlative research on automatic detection. The paper hasmade research on optimizing the automatic inspection system of piston rings.In the three-position and parallel system of inspecting the automotive pistonrings, CCD camera is unable to cover the complete piston ring in only one image.This paper rotate the camera to acquire the partial image, and calculate the degree oflight leakage by mosaicking images. The introduction of slip ring solve the windingproblem, camera can rotate continuously in the same direction. The paper will controlthe camera to rotate again if it missed images. The algorithm to calculate the width ofend gap is optimized to adapt to the uncertain positon and cracked image.The train piston rings automatic inspection system is constructed by IndustrialPersonal Computer and touch screen and PLC. The optimized algorithm canintelligently recognize the positon and the width of end gap. Man-machine interfacecan display results at real time. This instrument has accept by Institute of Qishuyanand applied in industrial field.Measurement uncertainty exists in any measurement result and generatesuncertain area near the specification limit. Traditionally, products are judged on thelimit principle, measurement results in the uncertain area may be misjudged. Thepaper apply ISO/TS14253-1in automatic inspection and separation system to reducethe misjudgments caused by measurement uncertainty.