Abstract:In order to measure the oil film thickness of camtappet contact accurately,a light interference measurement system of cam-tappet lubricating oil film was designed and manufactured.In this system,the eccentric ball-glass disc contact pair was used to simulate the point contact of cam-tappet,and the eccentric ball was driven to rotate by synchronous pulley,so as to realize the measurement of friction force and load in the process of eccentric ball movement.At the same time,the oil film thickness of eccentric round camtappet contact was measured by using multi-beam interferometric technology.The system was used to measure the oil film thickness and friction force of eccentric cam-tappet mechanism under different conditions.The results show that the film thickness is decreased with the increase of load under the same rotating speed and angle.The higher the rotating speed is,the thicker the film is,and the greater the inertia force at the “cam nose” is.Under the same conditions,when the eccentricity is large,the film thickness is higher in the range 0° to 90°and from 270° to 360°,and slightly lower in the range from 90° to 270°.With the increase of rotation speed under the same load,the position of the maximum friction force moves forward.