Elastohydrodynamic film thickness and temperature measurements in dynamically loaded concentrated contacts : eccentric cam-flat follower

This paper describes some results of local film thickness and temperature measurements in an eccentric cam-flat follower contact by means of miniature vapour deposited thin layer transducers. Complex transducer patterns can be realized by employing photolithography, allowing local measurements in axial direction. A full film will develop at relatively low speeds. At high speeds chemical reaction layer formation starts. Film thickness and temperature at both sides of the contact differed appreciably, thus invalidating the assumption of line contact. Under high loads and misalignment a constriction in the film thickness, typically for EHD contacts, appears at the heavy load side. Only after supporting the follower on a self-aligning elastic hinge, a line contact condition could be attained. Temperature variations of the follower surface were found to be moderate. The transducers worked well and have a satisfying life expectancy.