Development of Technique to Measure Instantaneous Slip Between Cam and Roller in Real Engine

Abstract

End-pivoted roller followers are a common type of valve actuation configurations in modern passenger vehicles. Considerable research work has gone into such valve actuation configurations with regards to average roller slippage, roller friction, and oil pressure, however, limited work has been done on the measurement of instantaneous slip. In this study, an instrumentation method is developed and implemented to study how irregular roller movements relative to the cam vary instantaneously. The technique avoids any major modifications to the rollers and test engine, allowing us to detect slip while simulating a live engine. Using this experimental technique, one can investigate instantaneous roller slip by studying the effects of different variables such as lubricant type, surface finish, temperature, cam profile and rotation speed.