Abstract: The invention relates to a rotating machine part having, in particular, a flat housing or base with an essentially cylindrical outer wall or with symmetrically distributed projections which are arranged in particular in the form of a star, in particular a rotor (1) of a cycloid propeller, the cylinder axis or rotor axis being the same as the rotation axis and the machine part or housing rotating in an atmosphere or a medium which is able to transmit heat to a sufficient extent to produce a required cooling effect on the machine part or housing or in its interior.

Abstract: An arrangement for mounting a cycloidal propeller is disclosed which has elastic support rings and elastic thrust rings. At least the elastic thrust rings are clamped between two frustoconical surfaces which are substantially parallel to each other. One surface is on a ring attached to the propeller base plate and the other is on a ring attached to the propeller foundation. The position of the rings may be changed to adjust the natural frequency of the mounting, for better damping of the forces from the propeller. The elastic support rings are preferably also clamped between parallel frustoconical surfaces. The angle of inclination of all the frustoconical surfaces in relation to the plane of the propeller base plate is between 32.degree.-38.degree..

Abstract: An installation for extracting useful work, such as driving an electric generator from a fluid stream, includes a platform rotatable about a central axis and supporting a plurality of blades or vanes, each of which is rotatable about its individual blade axis to vary the angle of attack between the blades and the fluid stream during each revolution of the platform. The blades are coupled together so that each blade executes a similar motion during each platform revolution and so that the angle of attack of the fluid stream relative to a given blade is substantially zero when the fluid stream direction is perpendicular to the plane including the central platform axis and the axis of the given blade, the amount of variation in blade angle of attack during each revolution is variable to compensate for variations in the fluid flow.

Abstract: A device for generating a thrust in a liquid utilizing rotating cylinders. The cylinders are mounted on a rotatable hub and rotate about their own axes relative to the hub. The relative rotation follows, preferably, a sinusoidal path for producing the thrust, and in particular, each cylinder undergoes a reversal in its direction of rotation after each half rotation of the hub. A common control bar is included which is connected to each cylinder and eccentrically with respect to the axis of rotation of the hub so that the points of reversal and the direction of thrust can be adjusted.