Vacuum Frictionless Mechanisms Based on the Principle of Controlled Elastic Deformation

Abstract

The idea of these mechanisms was born between 1970–1980 in the former USSR and it was realized by Professor A.T. Alexandrova. The group of Professor Alexandrova designed and manufactured different vacuum manipulators, vacuum drives, vacuum rotary-motion and linear-motion feedthroughs, gates and valves based on the principle of controlled elastic deformation. This work was pioneer in the field of vacuum technique and technology. In many cases the applicability of traditional gears, ball bearings and friction couples is limited in vacuum because of gas tribodesorption, wear of contacting surfaces, limited service life of friction couple (see Chapters 3 and 7). The solution of these problems can be found by controlling friction, wear and gas tribodesorption vacuum mechanisms as well as by use of frictionless mechanisms based on the principle of controlled elastic deformation. Not all vacuum mechanisms could be realized using controlled elastic deformation of vacuum mechanisms. Nevertheless, in many cases, for example for fastacting vacuum manipulators, transporting systems, precise positioning systems, bodiless vacuum gates and valves, and other small mechanisms, the use of controlled elastic deformation of vacuum mechanisms is very promising because of compactness, low weight and absence of interfacial friction. The elemental basis of vacuum mechanisms without friction couples consists of various hermetic driving tube elements of different configurations (as shown in Figure 9.1). These elements can be deformed by supplying compressed gas or liquid inside the tube elements under controlled pressure.