Abstract: A steam or vapor engine comprising a vapor generating apparatus, at least one cylinder with a piston working in the cylinder, and pipes and valves for supplying vapor from the vapor generating apparatus to a closed chamber, formed in the cylinder, and for discharging vapor from the cylinder chamber after a working stroke, and an apparatus for supplying an additive, which rapidly expands at the temperature of the vapor, to the cylinder chamber essentially simultaneously with the vapor.

Abstract: An improvement of a spring operated, reversibly rotatable body having a surface on which a flexible, elongated object, e.g. a wire or a band, can be wound, said body being connected with a spring which is stretched by the rotation of the body during the unwinding of said elongated object. The improvement includes a transmission between the elongated object and the spring, said transmission having a gearing ratio which is varied during the rotation of the body. The variable gearing ratio can be obtained by giving the surface of the rotatable body, along the axis of rotation, a varying distance to the axis of rotation. In a preferred embodiment, two rotatable bodies, are used, said bodies being connected by means of a traction wire which is wound on the surfaces of said bodies. One of the bodies is connected with the spring and the other with an output shaft.