Patent GB-1403325-A (GB)
Title: Mechanical drive device
IPC: F16F15/30
Filed: 1973-02-15
Abstract: 1403325 Reciprocating piston I C engines P VALERI 15 Feb 1973 [31 May 1972 31 Oct 1972] 7579/73 Heading F1B [Also in Division F2] A mechanical device for increasing the efficiency of a drive-shaft C comprises a pair of coaxial and opposed cylindrical bodies, A, A 1  provided with an elliptical rib D, D 1  respectively, on their outer surfaces and acting as pistons within a common cylinder B wherein, between internal opposite surfaces 11, 12 of the pistons, combustion chambers 13, 14 are provided, e.g. chambers of a two cylinder internal combustion engine. The pistons A, A 1  are mounted on and reciprocate along a shaped portion of the shaft C, which portion is non-circular, e.g. polygonal in cross-section as are the holes extending lengthwise of the pistons A, A 1  and housing the shaft C. The shaft C is supported at opposite ends in bearings allowing rotation together with pistons A, A 1  but not axial motion. The ribs D, D 1  move between pairs of inwardly projecting pins within the cylinder B so that axial movement of the pistons is accompanied by their rotation. Masses I, L are fixedly mounted on pistons A, A 1  through outwardly projecting arms M, N and each mass functions as a flywheel fixed to the corresponding piston. Semi-elliptical members F, F 1  (extending only 180 degrees as compared with the 360 degrees of the ribs, D, D 1 ) are fixedly mounted adjacent the ends of the pistons A, A 1  at a smaller inclination than the ribs D, D 1  and the masses, I, L move along these members F, Fi during alternate half-revolutions of the pistons A, A 1 ; Because of the smaller inclination of the members F, F 1  compared with the ribs D, D 1 , the power necessary to move the masses I, L along these members is less than it would be to move them along the ribs D, D 1  or to raise them vertically. In the case of the mass I, the rotary movement of shaft C is improved during the expansion stroke of the piston A by the free fall of the mass during 180 degrees rotation of the piston. During the next 180 degrees rotation with piston A in a passive stroke, the mass I rolls along the surface of member F needing less power than would be required for a free raising of the mass. The result is a positive power torque difference between the free downward motion and the upward rolling motion along the semi-elliptical member, which difference is transferred to the shaft C to increase the overall efficiency of the engine. Efficiency is still further increased by the similar and alternate operation of the other piston A 1 . In a modification, Fig. 5 (not shown), the piston shafts are provided with elliptical grooves instead of ribs and these are each engaged by a pair of pins or pivots which protrude radially inwards from the internal surface of the surrounding cylinder. Each of these pins or pivots acts on one of the two opposite wall surfaces of the groove. In further embodiments, Figs. 6 and 7 (not shown), the cylindrical bodies are mounted either on parallel shafts or on the same shaft, the shaft(s) being connected to a main driving shaft which may be the output shaft of another machine, e.g. an electric motor.