Meshing gears 1 and 2, of equal pitch diameter, rotate about fixed axes A and C. Connecting rods 4 and 5 are connected by turning pairs B and D to gears 1 and 2, and by turning pairs E to piston 3 which slides in fixed cylinder b. The dimensions of the links comply with the conditions: A͞B=C͞D and B͞E=D͞E. The angles made by lines AB and CD with axis y of the cylinder are equal and symmetrically located. When either gear 1 or 2 rotates, piston 3 reciprocates along axis y. If gears 1 and 2 are of equal mass, as are connecting rods 4 and 5, there will be no pressure on the cylinder walls due to forces of inertia of the links.
$2534$LrG,PM$