ACTIVE CONTACT PROBLEMS IN EPITROCHOID GENERATED FLOATING AXIS ORBITAL ROTARY PISTON MACHINES

The patterns of contact stresses and rolling-sliding motions at the ac tive contacts of the rotary piston machine (ROPIMA) type hydrostatic u nits, having ''epitrochoid'' generated rotor-stator set with epicyclic motion of the 'floating axis'' rotor, have been investigated. A dimen sionless analytical technique, based on Hertz's contact theory, has be en developed. As the stress problem in such machines is a statically i ndeterminate type a numerical iterative scheme has been adopted for so lutions. It is found that the gaps are generated even at the ''transit ion contacts.'' Effects of profile modifications on these constraints have been studied. Some results have also been supported experimentall y. Optimum values of modifications have also been suggested in most ge neralized form.