Patent ID: 6799955
Filing Date: 2004-10-05
Classification: F01C

Abstract:
A rotary machine comprising:a housing with spaced apart end walls for defining a chamber; a two-lobe elliptical or lenticular rotor assembly having curved faces meeting at symmetrically opposed apices, said rotor assembly having two parallel end faces extending between said curved faces, each of said parallel end faces facing one of said end walls, said rotor assembly disposed in said chamber for eccentric rotation therein, said rotor assembly further having an even number of eight or more straight cams in at least one of said parallel end faces arranged about a center of said rotor assembly, each of said straight cams defining an edge ending at a distance from said rotor center; a rotor guide assembly extending from at least one of said end walls, said rotor guide assembly including four or more arc cams, each of said four or more arc cams being cylindrical in shape over a portion thereof, each of said four or more arc cams having a radius Rp over said portion, each of said four or more arc cams extending through at least one of said parallel end faces having said straight cams, said four or more arc cams engaging said straight cams during said eccentric rotation of said rotor assembly, each of said arc cams having a center longitudinal axis; a shaft having a center longitudinal axis, said center longitudinal axis of said shaft being offset from said center of said rotor assembly by an offset distance RC1, said shaft extending through said chamber and rotatably mounted in one or both of said endwalls, said shaft further being centered between said four or more arc cams such that the distance RC2 of said center longitudinal axis of said shaft to each of said center longitudinal axis of said four or more arc cams is equal to said offset distance RC1, said shaft including at least one eccentric bearing for forming driving contact between said shaft and said rotor assembly, said eccentric bearing having longitudinal center passing through said center of said rotor assembly; a point of engagement of each of said arc cams with either of two engaging straight cams of said eight or more straight cams, said point of engagement having distance from said center of said rotor assembly, said point of engagement having a rotor assembly position, said rotor assembly position having an angle (180âˆ’&agr;) between said center of said rotor assembly to said arc cam center longitudinal axis measured from said shaft center longitudinal axis, said point of engagement having said distance from said center of said rotor assembly equal to RC12+R1C22-2&it;â€ƒ&it;RC1&it;R1C2&it;cos&af;(180-Î±)+RP2.