Abstract: A compound rotary and/or linear motor comprises two interposed magnet systems of which at least one is variable by an electronic control system to generate rotary and/or linear motion of the other. One of the two magnet systems consists of axially consecutive arrangements, preferably rings, of electrically separate magnet poles. The other magnet system contains at least one pair of magnet poles. The electronic control system is designed optionally or according to program to generate rotary motion by sequentially energizing consecutive magnets in a ring, to generate linear motion by sequentially energizing axially consecutive magnets and to generate a combined linear and/or rotary motion by sequentially energizing consecutive magnets forming a helix.

Abstract: The invention provides a high vacuum pump system of high pumping speed in which the surfaces that are to be cooled are coated with adsorbents in such a manner that it is possible to bale out and activate the coatings at temperatures between 250.degree. and 400.degree. C and then to use them for the maintenance or repeated generation of high vacua containing no hydrocarbons down to pressures as low as about 10.sup.-8 torrs.