Tribometer Design of Slide Bearings under Micro-Load

A type of tribometer for experimental study of tribological performance of journal bearings under micro-load was developed, which utilizes the method of load counterpoise to obtain mechanics equilibrium state of the test rig so as to apply load from zero. A laser device and a PSD sensor were used to measure the displacement and friction force with high precision without contact. The friction coefficient is obtained from the frictional angle of the cantilever and displacement of PSD sensor. Two methods were used for the measurement of friction coefficient, friction angle and frictional torque equilibrium. The former measures the angle resulting from friction, and the latter utilizes the exterior torque to poise the rig mechanics state under the rotating condition. The zero location on PSD is at the tail end of test process. Through reaching one side weight limitation with pulley at the static state, calibration of load was completed. The tribometer can measure friction, stick-slip of journal bearings under micro-load. Furthermore, measurements of wider range of load and /or friction coefficient were achieved by setting the structure parameters of the tribometer. With data sampling and processing capability, bearing bulk temperature and friction coefficient can be obtained continuously with adjustable load or/and speed.