EDWARD C MENDLER
Broker in Wayland, MA

4666383, May 19, 1987

Apr 26, 1984

6/632725

Edward C. Mendler - Wayland MA

F01C 1902

418115

Rotary machines of the type having a fluid chamber of changing volume, e. g. as ion an engine or pump, in which two rotors rotate in the same direction; a cylindrical surface of the first rotor of substantial arcuate extent, of radius substantially equal to the radius of its bore is arranged for sealing relationship throughout a chamber-defining range of rotation, with both its bore wall and with a surface of the second rotor; and the surface of the second rotor has a progressively changing radius to cause the chamber volume to progressively change during rotation. For forming multiple chambers, each subject to successive compression and expansion, each of the rotors has a transition surface preceding its large cylindrical surface and a transition surface following its large cylindrical surface, with an apex seal formed at each end of each large cylindrical surface. Preferably a small cylindrical surface on each rotor between the two transition surfaces seals against the large cylindrical surface of the other rotor during rotation. Useful in other machines as well, the rotor carries movable sealing members which apply against an opposed surface sealing pressure that decreases in magnitude with increase in rotational velocity, with restraint to control sealing movement.