Measurement of Piston Pin-boss Oil-film Pressure in Engine Operating Condition using a Thin-film Sensor

Abstract

In order to know a stress distribution in piston-pin boss in engine operating condition, a new thin-film sensor was developed to measure the oil-film pressure in pin-bosses. The sensor which has φ0.45mm sensing part and 7μm in total thickness was deposited by sputtering on a piston pin surface. This kind of sensors succeeded already in measuring oil-film pressure distribution in engine bearing. However, the result was affected by high temperature in piston pin, especially by temperature dependence of sensor sensitivity. For obtaining the stable characteristics, nitride layers were applied as protection and insulation layers. This paper presents the new structure of sensors and measurement results.